Imaging Of The Urinary Tract DR.SULTAN ALHAJAHJEH RADIOLOGY DEPARTMENT JORDAN UNIVERSITY HOSPITAL
Jul 16, 2015
Imaging Of The
Urinary Tract DRSULTAN ALHAJAHJEH
RADIOLOGY DEPARTMENT
JORDAN UNIVERSITY HOSPITAL
Anatomy of the urinary tract
Pelvic calacyeal system
There are usually seven pairs of minor calyces
Minor calyx pairs combine to form two or three major calyceswhich in turn drain via their infundibula to the pelvis
The pelvis may be intrarenal or partially or entirely extrarenal
The hilum of the kidney lies medially that of the left at L1 vertebral level and that of the right slightly lower at L1L2 level owing to the bulk of the liver above
At the hilum the pelvis lies posteriorly and the renal vein anteriorly with the artery in between
Anatomy of the urinary tract
The ureters
Each is 25-30 cm long and is described as having a pelvis and
abdominal pelvic and intravesical parts
the ureter has a diameter of about 3 mm but is narrower at the
following three sites
The junction of the pelvis and ureter
The pelvic brim
The intravesical ureter where it runs through the muscular bladder
wall
Anatomy of the urinary tract
1 Right upper-pole (major) calyx
2 Right middle (major) calyx
3 Right lower-pole (major) calyx
4 Left upper-pole (major) calyx
5 Left lower-pole (major) calyx
6 Minor calyx (infundibulum of)
7 Papilla
8 Infundibulum
9 Fornix
10 Bifid left renal pelvis
11 Right renal pelvis
12 Right ureter
13 Left ureter vascular impression
14 Upper pole right kidney
15 Right psoas outline
16 Gas in body of stomach
17 Gas in transverse colon
18 Intravesical ureter
Anatomy of the urinary tract
Bladder This is a pyramidal muscular organ when empty It has a triangular-shaped base
posteriorly
The ureters enter the posterolateral angles and the urethra leaves inferiorly at the narrow neck which is surrounded by the (involuntary) internal urethral sphincter
It has one superior and two inferolateral walls which meet at an apex behind the pubic symphysiss
In the female the body of the uterus rests on its posteronotsuperior surface and the cervix and vagina are posterior with the rectum behind
In the male the neck is fused with the prostate
The bladder is supplied via the internal iliac artery via superior and inferior vesicalarteries
Urinary bladder
rectum
prostate
Anatomy of the urinary tract
The urethra The male urethra runs from the internal urethral sphincter at the neck
of the bladder to the external urethral orifice at the tip of the penis
The posterior urethra comprises the prostatic and membranous
urethra and the anterior part comprises the bulbous and penile
urethra
In females This is 4 cm long It extends from the internal urethral
sphincter at the bladder neck through the urogenital diaphragm to
the external urethral meatus anterior to the vaginal opening
1Balloon of catheter in
navicular fossa
2 Penile urethra
3 Bulbous urethra
4 Membranous urethra
5 Impression of verumontanum in
prostatic urethra
6 Filling of utricle (not usually seen)
7 Air bubbles in
contrast
Imaging techniques of the urinary
tract
kub
Ivu
Mcug
Ultrasound
Ascending urethrogram
Mri
Pelvicalyceal system
Duplex collecting system
Congenital ureteropelvic junction (UPJ) obstruction
Congenital megacalyces
(PYELO)Calyceal diverticulum
Renal papillary necrosis (RPN)
Pyonephrosis
Duplex collecting system
It is one of the most common congenital renal tract abnormalities 4-
5 It is characterised by incomplete fusion of upper and lower pole
moieties resulting in complete or incomplete duplication of the
collecting system
duplex collecting system - a duplex kidney draining into
single ureter - ie duplex kidneys duplication pelvicalcyeal systems uniting at the pelvi-ureteric junction (PUJ)
bifid ureter (ureter fissus) - two ureters that unite before emptying into
the bladder
double ureter (complete duplication) two ureters that drain separately
into the bladder or genital tract
Duplex collecting system
Orthotopic ureter drains lower pole and
enters bladder near trigone
Ectopic ureter drains upper pole and enters
bladder inferiorly and medially (Weigert-
Meyer rule) the ectopic ureter may be
stenotic and obstructed
Spot film taken during an IVP shows
bilateral duplex kidneys
On the left side the ureters have
fused at the level of L3 vertebra
On the right side both ureters have
opened into the bladder
Fluoroscopy MCU Grade 5 reflux with
double excretory system on the left side
Fusion of both ureters right before the
bladder (cystoscopy confirmed the
presence of only 2 ostia in the bladder)
Hydronephrosis
Drooping lily sign - a urographic
sign of duplicated renal
collecting system It refers to the
inferolateral displacement of
the opacified lower pole moiety
due to an obstructed (and
relatively unopacified) upper pole moiety
In duplicated collecting system
it is classically the upper pole
ureter that is obstructed due to
a ureterocoele and the lower
pole ureter that refluxes as
described by the Weigert-Meyer
law
left sided duplicated collecting system
with a distorted lower pole moiety from
obstructed upper pole This results in the
so called drooping lilly sign
Congenital ureteropelvic junction
(UPJ) obstruction
Most common congenital anomaly of the GU tract in neonates 20 of
obstructions are bilateral
bull Intrinsic 80 defect in circular muscle bundle
of renal pelvis
bull Extrinsic 20 renal vessels (lower pole artery
or vein)
The estimated incidence in pediatric population is at ~1 per 1000-2000
newborns and there is a recognised predilection towards the left side
(~67 of cases) and a male predominance
Congenital ureteropelvic junction
(UPJ) obstruction
asymptomatic or When symptomatic symptoms include recurrent urinary tract infections stone formation and even a palpable flank mass
Ultrasound
will often show a dilated renal pelvis with a collapsed proximal ureter
with Doppler sonography the obstructed kidneys can show higher RIs (resistive indices)
CT
May show evidence of hydronephrosis +- calyectasis with collapsed ureters Useful for assessing crossing vessels at the PUJ especially when surgical intervention is planned
Congenital ureteropelvic junction
(UPJ) obstruction Left sided
hydronephrosis is seen
with dilated and
ballooned out left renal
pelvis
Left pelviureteric
junction is markedly
narrowed with probably delayed contrast
excretion into left ureter
Congenital ureteropelvic junction
(UPJ) obstruction Right PUJ obstruction
Dilated renal pelvis and renal
calices with normal ureter
Congenital megacalyces
is an incidental finding which mimics hydronephrosis It is a result of
underdevelopment of the renal medullary pyramids with resultant
enlargement of the calyces It it more frequently seen in males
The enlarged floppy calyces predispose to stasis infection and
calculus formation There is an association with congenital
megaureter
due to the lack of normal medullary pyramids not only are the
calyces enlarged but they lack the normal imprint from the papillae
thus having a flat appearance
Congenital megacalyces
The renal pelvis is of normal size helping to distinguish megacalyces
from hydronephrosis
In addition to enlargement of the calyces there is often also
polycalycosis (increased number of calyces) they are crowded
and multifaceted with a mosaic-like appearance
Congenital megacalyces
This 10-month old male had a large right
kidney thought to be due to tumour
There are more than the usual number of
calyces
(PYELO)Calyceal diverticulum
Outpouching of calyx into corticomedullary region
May also arise from renal pelvis or an infundibulum
Usually asymptomatic but patients may develop calculi
bull Type I originates from minor calyx
bull Type II originates from infundibulum
bull Type III originates from renal pelvis
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Anatomy of the urinary tract
Pelvic calacyeal system
There are usually seven pairs of minor calyces
Minor calyx pairs combine to form two or three major calyceswhich in turn drain via their infundibula to the pelvis
The pelvis may be intrarenal or partially or entirely extrarenal
The hilum of the kidney lies medially that of the left at L1 vertebral level and that of the right slightly lower at L1L2 level owing to the bulk of the liver above
At the hilum the pelvis lies posteriorly and the renal vein anteriorly with the artery in between
Anatomy of the urinary tract
The ureters
Each is 25-30 cm long and is described as having a pelvis and
abdominal pelvic and intravesical parts
the ureter has a diameter of about 3 mm but is narrower at the
following three sites
The junction of the pelvis and ureter
The pelvic brim
The intravesical ureter where it runs through the muscular bladder
wall
Anatomy of the urinary tract
1 Right upper-pole (major) calyx
2 Right middle (major) calyx
3 Right lower-pole (major) calyx
4 Left upper-pole (major) calyx
5 Left lower-pole (major) calyx
6 Minor calyx (infundibulum of)
7 Papilla
8 Infundibulum
9 Fornix
10 Bifid left renal pelvis
11 Right renal pelvis
12 Right ureter
13 Left ureter vascular impression
14 Upper pole right kidney
15 Right psoas outline
16 Gas in body of stomach
17 Gas in transverse colon
18 Intravesical ureter
Anatomy of the urinary tract
Bladder This is a pyramidal muscular organ when empty It has a triangular-shaped base
posteriorly
The ureters enter the posterolateral angles and the urethra leaves inferiorly at the narrow neck which is surrounded by the (involuntary) internal urethral sphincter
It has one superior and two inferolateral walls which meet at an apex behind the pubic symphysiss
In the female the body of the uterus rests on its posteronotsuperior surface and the cervix and vagina are posterior with the rectum behind
In the male the neck is fused with the prostate
The bladder is supplied via the internal iliac artery via superior and inferior vesicalarteries
Urinary bladder
rectum
prostate
Anatomy of the urinary tract
The urethra The male urethra runs from the internal urethral sphincter at the neck
of the bladder to the external urethral orifice at the tip of the penis
The posterior urethra comprises the prostatic and membranous
urethra and the anterior part comprises the bulbous and penile
urethra
In females This is 4 cm long It extends from the internal urethral
sphincter at the bladder neck through the urogenital diaphragm to
the external urethral meatus anterior to the vaginal opening
1Balloon of catheter in
navicular fossa
2 Penile urethra
3 Bulbous urethra
4 Membranous urethra
5 Impression of verumontanum in
prostatic urethra
6 Filling of utricle (not usually seen)
7 Air bubbles in
contrast
Imaging techniques of the urinary
tract
kub
Ivu
Mcug
Ultrasound
Ascending urethrogram
Mri
Pelvicalyceal system
Duplex collecting system
Congenital ureteropelvic junction (UPJ) obstruction
Congenital megacalyces
(PYELO)Calyceal diverticulum
Renal papillary necrosis (RPN)
Pyonephrosis
Duplex collecting system
It is one of the most common congenital renal tract abnormalities 4-
5 It is characterised by incomplete fusion of upper and lower pole
moieties resulting in complete or incomplete duplication of the
collecting system
duplex collecting system - a duplex kidney draining into
single ureter - ie duplex kidneys duplication pelvicalcyeal systems uniting at the pelvi-ureteric junction (PUJ)
bifid ureter (ureter fissus) - two ureters that unite before emptying into
the bladder
double ureter (complete duplication) two ureters that drain separately
into the bladder or genital tract
Duplex collecting system
Orthotopic ureter drains lower pole and
enters bladder near trigone
Ectopic ureter drains upper pole and enters
bladder inferiorly and medially (Weigert-
Meyer rule) the ectopic ureter may be
stenotic and obstructed
Spot film taken during an IVP shows
bilateral duplex kidneys
On the left side the ureters have
fused at the level of L3 vertebra
On the right side both ureters have
opened into the bladder
Fluoroscopy MCU Grade 5 reflux with
double excretory system on the left side
Fusion of both ureters right before the
bladder (cystoscopy confirmed the
presence of only 2 ostia in the bladder)
Hydronephrosis
Drooping lily sign - a urographic
sign of duplicated renal
collecting system It refers to the
inferolateral displacement of
the opacified lower pole moiety
due to an obstructed (and
relatively unopacified) upper pole moiety
In duplicated collecting system
it is classically the upper pole
ureter that is obstructed due to
a ureterocoele and the lower
pole ureter that refluxes as
described by the Weigert-Meyer
law
left sided duplicated collecting system
with a distorted lower pole moiety from
obstructed upper pole This results in the
so called drooping lilly sign
Congenital ureteropelvic junction
(UPJ) obstruction
Most common congenital anomaly of the GU tract in neonates 20 of
obstructions are bilateral
bull Intrinsic 80 defect in circular muscle bundle
of renal pelvis
bull Extrinsic 20 renal vessels (lower pole artery
or vein)
The estimated incidence in pediatric population is at ~1 per 1000-2000
newborns and there is a recognised predilection towards the left side
(~67 of cases) and a male predominance
Congenital ureteropelvic junction
(UPJ) obstruction
asymptomatic or When symptomatic symptoms include recurrent urinary tract infections stone formation and even a palpable flank mass
Ultrasound
will often show a dilated renal pelvis with a collapsed proximal ureter
with Doppler sonography the obstructed kidneys can show higher RIs (resistive indices)
CT
May show evidence of hydronephrosis +- calyectasis with collapsed ureters Useful for assessing crossing vessels at the PUJ especially when surgical intervention is planned
Congenital ureteropelvic junction
(UPJ) obstruction Left sided
hydronephrosis is seen
with dilated and
ballooned out left renal
pelvis
Left pelviureteric
junction is markedly
narrowed with probably delayed contrast
excretion into left ureter
Congenital ureteropelvic junction
(UPJ) obstruction Right PUJ obstruction
Dilated renal pelvis and renal
calices with normal ureter
Congenital megacalyces
is an incidental finding which mimics hydronephrosis It is a result of
underdevelopment of the renal medullary pyramids with resultant
enlargement of the calyces It it more frequently seen in males
The enlarged floppy calyces predispose to stasis infection and
calculus formation There is an association with congenital
megaureter
due to the lack of normal medullary pyramids not only are the
calyces enlarged but they lack the normal imprint from the papillae
thus having a flat appearance
Congenital megacalyces
The renal pelvis is of normal size helping to distinguish megacalyces
from hydronephrosis
In addition to enlargement of the calyces there is often also
polycalycosis (increased number of calyces) they are crowded
and multifaceted with a mosaic-like appearance
Congenital megacalyces
This 10-month old male had a large right
kidney thought to be due to tumour
There are more than the usual number of
calyces
(PYELO)Calyceal diverticulum
Outpouching of calyx into corticomedullary region
May also arise from renal pelvis or an infundibulum
Usually asymptomatic but patients may develop calculi
bull Type I originates from minor calyx
bull Type II originates from infundibulum
bull Type III originates from renal pelvis
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Anatomy of the urinary tract
The ureters
Each is 25-30 cm long and is described as having a pelvis and
abdominal pelvic and intravesical parts
the ureter has a diameter of about 3 mm but is narrower at the
following three sites
The junction of the pelvis and ureter
The pelvic brim
The intravesical ureter where it runs through the muscular bladder
wall
Anatomy of the urinary tract
1 Right upper-pole (major) calyx
2 Right middle (major) calyx
3 Right lower-pole (major) calyx
4 Left upper-pole (major) calyx
5 Left lower-pole (major) calyx
6 Minor calyx (infundibulum of)
7 Papilla
8 Infundibulum
9 Fornix
10 Bifid left renal pelvis
11 Right renal pelvis
12 Right ureter
13 Left ureter vascular impression
14 Upper pole right kidney
15 Right psoas outline
16 Gas in body of stomach
17 Gas in transverse colon
18 Intravesical ureter
Anatomy of the urinary tract
Bladder This is a pyramidal muscular organ when empty It has a triangular-shaped base
posteriorly
The ureters enter the posterolateral angles and the urethra leaves inferiorly at the narrow neck which is surrounded by the (involuntary) internal urethral sphincter
It has one superior and two inferolateral walls which meet at an apex behind the pubic symphysiss
In the female the body of the uterus rests on its posteronotsuperior surface and the cervix and vagina are posterior with the rectum behind
In the male the neck is fused with the prostate
The bladder is supplied via the internal iliac artery via superior and inferior vesicalarteries
Urinary bladder
rectum
prostate
Anatomy of the urinary tract
The urethra The male urethra runs from the internal urethral sphincter at the neck
of the bladder to the external urethral orifice at the tip of the penis
The posterior urethra comprises the prostatic and membranous
urethra and the anterior part comprises the bulbous and penile
urethra
In females This is 4 cm long It extends from the internal urethral
sphincter at the bladder neck through the urogenital diaphragm to
the external urethral meatus anterior to the vaginal opening
1Balloon of catheter in
navicular fossa
2 Penile urethra
3 Bulbous urethra
4 Membranous urethra
5 Impression of verumontanum in
prostatic urethra
6 Filling of utricle (not usually seen)
7 Air bubbles in
contrast
Imaging techniques of the urinary
tract
kub
Ivu
Mcug
Ultrasound
Ascending urethrogram
Mri
Pelvicalyceal system
Duplex collecting system
Congenital ureteropelvic junction (UPJ) obstruction
Congenital megacalyces
(PYELO)Calyceal diverticulum
Renal papillary necrosis (RPN)
Pyonephrosis
Duplex collecting system
It is one of the most common congenital renal tract abnormalities 4-
5 It is characterised by incomplete fusion of upper and lower pole
moieties resulting in complete or incomplete duplication of the
collecting system
duplex collecting system - a duplex kidney draining into
single ureter - ie duplex kidneys duplication pelvicalcyeal systems uniting at the pelvi-ureteric junction (PUJ)
bifid ureter (ureter fissus) - two ureters that unite before emptying into
the bladder
double ureter (complete duplication) two ureters that drain separately
into the bladder or genital tract
Duplex collecting system
Orthotopic ureter drains lower pole and
enters bladder near trigone
Ectopic ureter drains upper pole and enters
bladder inferiorly and medially (Weigert-
Meyer rule) the ectopic ureter may be
stenotic and obstructed
Spot film taken during an IVP shows
bilateral duplex kidneys
On the left side the ureters have
fused at the level of L3 vertebra
On the right side both ureters have
opened into the bladder
Fluoroscopy MCU Grade 5 reflux with
double excretory system on the left side
Fusion of both ureters right before the
bladder (cystoscopy confirmed the
presence of only 2 ostia in the bladder)
Hydronephrosis
Drooping lily sign - a urographic
sign of duplicated renal
collecting system It refers to the
inferolateral displacement of
the opacified lower pole moiety
due to an obstructed (and
relatively unopacified) upper pole moiety
In duplicated collecting system
it is classically the upper pole
ureter that is obstructed due to
a ureterocoele and the lower
pole ureter that refluxes as
described by the Weigert-Meyer
law
left sided duplicated collecting system
with a distorted lower pole moiety from
obstructed upper pole This results in the
so called drooping lilly sign
Congenital ureteropelvic junction
(UPJ) obstruction
Most common congenital anomaly of the GU tract in neonates 20 of
obstructions are bilateral
bull Intrinsic 80 defect in circular muscle bundle
of renal pelvis
bull Extrinsic 20 renal vessels (lower pole artery
or vein)
The estimated incidence in pediatric population is at ~1 per 1000-2000
newborns and there is a recognised predilection towards the left side
(~67 of cases) and a male predominance
Congenital ureteropelvic junction
(UPJ) obstruction
asymptomatic or When symptomatic symptoms include recurrent urinary tract infections stone formation and even a palpable flank mass
Ultrasound
will often show a dilated renal pelvis with a collapsed proximal ureter
with Doppler sonography the obstructed kidneys can show higher RIs (resistive indices)
CT
May show evidence of hydronephrosis +- calyectasis with collapsed ureters Useful for assessing crossing vessels at the PUJ especially when surgical intervention is planned
Congenital ureteropelvic junction
(UPJ) obstruction Left sided
hydronephrosis is seen
with dilated and
ballooned out left renal
pelvis
Left pelviureteric
junction is markedly
narrowed with probably delayed contrast
excretion into left ureter
Congenital ureteropelvic junction
(UPJ) obstruction Right PUJ obstruction
Dilated renal pelvis and renal
calices with normal ureter
Congenital megacalyces
is an incidental finding which mimics hydronephrosis It is a result of
underdevelopment of the renal medullary pyramids with resultant
enlargement of the calyces It it more frequently seen in males
The enlarged floppy calyces predispose to stasis infection and
calculus formation There is an association with congenital
megaureter
due to the lack of normal medullary pyramids not only are the
calyces enlarged but they lack the normal imprint from the papillae
thus having a flat appearance
Congenital megacalyces
The renal pelvis is of normal size helping to distinguish megacalyces
from hydronephrosis
In addition to enlargement of the calyces there is often also
polycalycosis (increased number of calyces) they are crowded
and multifaceted with a mosaic-like appearance
Congenital megacalyces
This 10-month old male had a large right
kidney thought to be due to tumour
There are more than the usual number of
calyces
(PYELO)Calyceal diverticulum
Outpouching of calyx into corticomedullary region
May also arise from renal pelvis or an infundibulum
Usually asymptomatic but patients may develop calculi
bull Type I originates from minor calyx
bull Type II originates from infundibulum
bull Type III originates from renal pelvis
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Anatomy of the urinary tract
1 Right upper-pole (major) calyx
2 Right middle (major) calyx
3 Right lower-pole (major) calyx
4 Left upper-pole (major) calyx
5 Left lower-pole (major) calyx
6 Minor calyx (infundibulum of)
7 Papilla
8 Infundibulum
9 Fornix
10 Bifid left renal pelvis
11 Right renal pelvis
12 Right ureter
13 Left ureter vascular impression
14 Upper pole right kidney
15 Right psoas outline
16 Gas in body of stomach
17 Gas in transverse colon
18 Intravesical ureter
Anatomy of the urinary tract
Bladder This is a pyramidal muscular organ when empty It has a triangular-shaped base
posteriorly
The ureters enter the posterolateral angles and the urethra leaves inferiorly at the narrow neck which is surrounded by the (involuntary) internal urethral sphincter
It has one superior and two inferolateral walls which meet at an apex behind the pubic symphysiss
In the female the body of the uterus rests on its posteronotsuperior surface and the cervix and vagina are posterior with the rectum behind
In the male the neck is fused with the prostate
The bladder is supplied via the internal iliac artery via superior and inferior vesicalarteries
Urinary bladder
rectum
prostate
Anatomy of the urinary tract
The urethra The male urethra runs from the internal urethral sphincter at the neck
of the bladder to the external urethral orifice at the tip of the penis
The posterior urethra comprises the prostatic and membranous
urethra and the anterior part comprises the bulbous and penile
urethra
In females This is 4 cm long It extends from the internal urethral
sphincter at the bladder neck through the urogenital diaphragm to
the external urethral meatus anterior to the vaginal opening
1Balloon of catheter in
navicular fossa
2 Penile urethra
3 Bulbous urethra
4 Membranous urethra
5 Impression of verumontanum in
prostatic urethra
6 Filling of utricle (not usually seen)
7 Air bubbles in
contrast
Imaging techniques of the urinary
tract
kub
Ivu
Mcug
Ultrasound
Ascending urethrogram
Mri
Pelvicalyceal system
Duplex collecting system
Congenital ureteropelvic junction (UPJ) obstruction
Congenital megacalyces
(PYELO)Calyceal diverticulum
Renal papillary necrosis (RPN)
Pyonephrosis
Duplex collecting system
It is one of the most common congenital renal tract abnormalities 4-
5 It is characterised by incomplete fusion of upper and lower pole
moieties resulting in complete or incomplete duplication of the
collecting system
duplex collecting system - a duplex kidney draining into
single ureter - ie duplex kidneys duplication pelvicalcyeal systems uniting at the pelvi-ureteric junction (PUJ)
bifid ureter (ureter fissus) - two ureters that unite before emptying into
the bladder
double ureter (complete duplication) two ureters that drain separately
into the bladder or genital tract
Duplex collecting system
Orthotopic ureter drains lower pole and
enters bladder near trigone
Ectopic ureter drains upper pole and enters
bladder inferiorly and medially (Weigert-
Meyer rule) the ectopic ureter may be
stenotic and obstructed
Spot film taken during an IVP shows
bilateral duplex kidneys
On the left side the ureters have
fused at the level of L3 vertebra
On the right side both ureters have
opened into the bladder
Fluoroscopy MCU Grade 5 reflux with
double excretory system on the left side
Fusion of both ureters right before the
bladder (cystoscopy confirmed the
presence of only 2 ostia in the bladder)
Hydronephrosis
Drooping lily sign - a urographic
sign of duplicated renal
collecting system It refers to the
inferolateral displacement of
the opacified lower pole moiety
due to an obstructed (and
relatively unopacified) upper pole moiety
In duplicated collecting system
it is classically the upper pole
ureter that is obstructed due to
a ureterocoele and the lower
pole ureter that refluxes as
described by the Weigert-Meyer
law
left sided duplicated collecting system
with a distorted lower pole moiety from
obstructed upper pole This results in the
so called drooping lilly sign
Congenital ureteropelvic junction
(UPJ) obstruction
Most common congenital anomaly of the GU tract in neonates 20 of
obstructions are bilateral
bull Intrinsic 80 defect in circular muscle bundle
of renal pelvis
bull Extrinsic 20 renal vessels (lower pole artery
or vein)
The estimated incidence in pediatric population is at ~1 per 1000-2000
newborns and there is a recognised predilection towards the left side
(~67 of cases) and a male predominance
Congenital ureteropelvic junction
(UPJ) obstruction
asymptomatic or When symptomatic symptoms include recurrent urinary tract infections stone formation and even a palpable flank mass
Ultrasound
will often show a dilated renal pelvis with a collapsed proximal ureter
with Doppler sonography the obstructed kidneys can show higher RIs (resistive indices)
CT
May show evidence of hydronephrosis +- calyectasis with collapsed ureters Useful for assessing crossing vessels at the PUJ especially when surgical intervention is planned
Congenital ureteropelvic junction
(UPJ) obstruction Left sided
hydronephrosis is seen
with dilated and
ballooned out left renal
pelvis
Left pelviureteric
junction is markedly
narrowed with probably delayed contrast
excretion into left ureter
Congenital ureteropelvic junction
(UPJ) obstruction Right PUJ obstruction
Dilated renal pelvis and renal
calices with normal ureter
Congenital megacalyces
is an incidental finding which mimics hydronephrosis It is a result of
underdevelopment of the renal medullary pyramids with resultant
enlargement of the calyces It it more frequently seen in males
The enlarged floppy calyces predispose to stasis infection and
calculus formation There is an association with congenital
megaureter
due to the lack of normal medullary pyramids not only are the
calyces enlarged but they lack the normal imprint from the papillae
thus having a flat appearance
Congenital megacalyces
The renal pelvis is of normal size helping to distinguish megacalyces
from hydronephrosis
In addition to enlargement of the calyces there is often also
polycalycosis (increased number of calyces) they are crowded
and multifaceted with a mosaic-like appearance
Congenital megacalyces
This 10-month old male had a large right
kidney thought to be due to tumour
There are more than the usual number of
calyces
(PYELO)Calyceal diverticulum
Outpouching of calyx into corticomedullary region
May also arise from renal pelvis or an infundibulum
Usually asymptomatic but patients may develop calculi
bull Type I originates from minor calyx
bull Type II originates from infundibulum
bull Type III originates from renal pelvis
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
1 Right upper-pole (major) calyx
2 Right middle (major) calyx
3 Right lower-pole (major) calyx
4 Left upper-pole (major) calyx
5 Left lower-pole (major) calyx
6 Minor calyx (infundibulum of)
7 Papilla
8 Infundibulum
9 Fornix
10 Bifid left renal pelvis
11 Right renal pelvis
12 Right ureter
13 Left ureter vascular impression
14 Upper pole right kidney
15 Right psoas outline
16 Gas in body of stomach
17 Gas in transverse colon
18 Intravesical ureter
Anatomy of the urinary tract
Bladder This is a pyramidal muscular organ when empty It has a triangular-shaped base
posteriorly
The ureters enter the posterolateral angles and the urethra leaves inferiorly at the narrow neck which is surrounded by the (involuntary) internal urethral sphincter
It has one superior and two inferolateral walls which meet at an apex behind the pubic symphysiss
In the female the body of the uterus rests on its posteronotsuperior surface and the cervix and vagina are posterior with the rectum behind
In the male the neck is fused with the prostate
The bladder is supplied via the internal iliac artery via superior and inferior vesicalarteries
Urinary bladder
rectum
prostate
Anatomy of the urinary tract
The urethra The male urethra runs from the internal urethral sphincter at the neck
of the bladder to the external urethral orifice at the tip of the penis
The posterior urethra comprises the prostatic and membranous
urethra and the anterior part comprises the bulbous and penile
urethra
In females This is 4 cm long It extends from the internal urethral
sphincter at the bladder neck through the urogenital diaphragm to
the external urethral meatus anterior to the vaginal opening
1Balloon of catheter in
navicular fossa
2 Penile urethra
3 Bulbous urethra
4 Membranous urethra
5 Impression of verumontanum in
prostatic urethra
6 Filling of utricle (not usually seen)
7 Air bubbles in
contrast
Imaging techniques of the urinary
tract
kub
Ivu
Mcug
Ultrasound
Ascending urethrogram
Mri
Pelvicalyceal system
Duplex collecting system
Congenital ureteropelvic junction (UPJ) obstruction
Congenital megacalyces
(PYELO)Calyceal diverticulum
Renal papillary necrosis (RPN)
Pyonephrosis
Duplex collecting system
It is one of the most common congenital renal tract abnormalities 4-
5 It is characterised by incomplete fusion of upper and lower pole
moieties resulting in complete or incomplete duplication of the
collecting system
duplex collecting system - a duplex kidney draining into
single ureter - ie duplex kidneys duplication pelvicalcyeal systems uniting at the pelvi-ureteric junction (PUJ)
bifid ureter (ureter fissus) - two ureters that unite before emptying into
the bladder
double ureter (complete duplication) two ureters that drain separately
into the bladder or genital tract
Duplex collecting system
Orthotopic ureter drains lower pole and
enters bladder near trigone
Ectopic ureter drains upper pole and enters
bladder inferiorly and medially (Weigert-
Meyer rule) the ectopic ureter may be
stenotic and obstructed
Spot film taken during an IVP shows
bilateral duplex kidneys
On the left side the ureters have
fused at the level of L3 vertebra
On the right side both ureters have
opened into the bladder
Fluoroscopy MCU Grade 5 reflux with
double excretory system on the left side
Fusion of both ureters right before the
bladder (cystoscopy confirmed the
presence of only 2 ostia in the bladder)
Hydronephrosis
Drooping lily sign - a urographic
sign of duplicated renal
collecting system It refers to the
inferolateral displacement of
the opacified lower pole moiety
due to an obstructed (and
relatively unopacified) upper pole moiety
In duplicated collecting system
it is classically the upper pole
ureter that is obstructed due to
a ureterocoele and the lower
pole ureter that refluxes as
described by the Weigert-Meyer
law
left sided duplicated collecting system
with a distorted lower pole moiety from
obstructed upper pole This results in the
so called drooping lilly sign
Congenital ureteropelvic junction
(UPJ) obstruction
Most common congenital anomaly of the GU tract in neonates 20 of
obstructions are bilateral
bull Intrinsic 80 defect in circular muscle bundle
of renal pelvis
bull Extrinsic 20 renal vessels (lower pole artery
or vein)
The estimated incidence in pediatric population is at ~1 per 1000-2000
newborns and there is a recognised predilection towards the left side
(~67 of cases) and a male predominance
Congenital ureteropelvic junction
(UPJ) obstruction
asymptomatic or When symptomatic symptoms include recurrent urinary tract infections stone formation and even a palpable flank mass
Ultrasound
will often show a dilated renal pelvis with a collapsed proximal ureter
with Doppler sonography the obstructed kidneys can show higher RIs (resistive indices)
CT
May show evidence of hydronephrosis +- calyectasis with collapsed ureters Useful for assessing crossing vessels at the PUJ especially when surgical intervention is planned
Congenital ureteropelvic junction
(UPJ) obstruction Left sided
hydronephrosis is seen
with dilated and
ballooned out left renal
pelvis
Left pelviureteric
junction is markedly
narrowed with probably delayed contrast
excretion into left ureter
Congenital ureteropelvic junction
(UPJ) obstruction Right PUJ obstruction
Dilated renal pelvis and renal
calices with normal ureter
Congenital megacalyces
is an incidental finding which mimics hydronephrosis It is a result of
underdevelopment of the renal medullary pyramids with resultant
enlargement of the calyces It it more frequently seen in males
The enlarged floppy calyces predispose to stasis infection and
calculus formation There is an association with congenital
megaureter
due to the lack of normal medullary pyramids not only are the
calyces enlarged but they lack the normal imprint from the papillae
thus having a flat appearance
Congenital megacalyces
The renal pelvis is of normal size helping to distinguish megacalyces
from hydronephrosis
In addition to enlargement of the calyces there is often also
polycalycosis (increased number of calyces) they are crowded
and multifaceted with a mosaic-like appearance
Congenital megacalyces
This 10-month old male had a large right
kidney thought to be due to tumour
There are more than the usual number of
calyces
(PYELO)Calyceal diverticulum
Outpouching of calyx into corticomedullary region
May also arise from renal pelvis or an infundibulum
Usually asymptomatic but patients may develop calculi
bull Type I originates from minor calyx
bull Type II originates from infundibulum
bull Type III originates from renal pelvis
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Anatomy of the urinary tract
Bladder This is a pyramidal muscular organ when empty It has a triangular-shaped base
posteriorly
The ureters enter the posterolateral angles and the urethra leaves inferiorly at the narrow neck which is surrounded by the (involuntary) internal urethral sphincter
It has one superior and two inferolateral walls which meet at an apex behind the pubic symphysiss
In the female the body of the uterus rests on its posteronotsuperior surface and the cervix and vagina are posterior with the rectum behind
In the male the neck is fused with the prostate
The bladder is supplied via the internal iliac artery via superior and inferior vesicalarteries
Urinary bladder
rectum
prostate
Anatomy of the urinary tract
The urethra The male urethra runs from the internal urethral sphincter at the neck
of the bladder to the external urethral orifice at the tip of the penis
The posterior urethra comprises the prostatic and membranous
urethra and the anterior part comprises the bulbous and penile
urethra
In females This is 4 cm long It extends from the internal urethral
sphincter at the bladder neck through the urogenital diaphragm to
the external urethral meatus anterior to the vaginal opening
1Balloon of catheter in
navicular fossa
2 Penile urethra
3 Bulbous urethra
4 Membranous urethra
5 Impression of verumontanum in
prostatic urethra
6 Filling of utricle (not usually seen)
7 Air bubbles in
contrast
Imaging techniques of the urinary
tract
kub
Ivu
Mcug
Ultrasound
Ascending urethrogram
Mri
Pelvicalyceal system
Duplex collecting system
Congenital ureteropelvic junction (UPJ) obstruction
Congenital megacalyces
(PYELO)Calyceal diverticulum
Renal papillary necrosis (RPN)
Pyonephrosis
Duplex collecting system
It is one of the most common congenital renal tract abnormalities 4-
5 It is characterised by incomplete fusion of upper and lower pole
moieties resulting in complete or incomplete duplication of the
collecting system
duplex collecting system - a duplex kidney draining into
single ureter - ie duplex kidneys duplication pelvicalcyeal systems uniting at the pelvi-ureteric junction (PUJ)
bifid ureter (ureter fissus) - two ureters that unite before emptying into
the bladder
double ureter (complete duplication) two ureters that drain separately
into the bladder or genital tract
Duplex collecting system
Orthotopic ureter drains lower pole and
enters bladder near trigone
Ectopic ureter drains upper pole and enters
bladder inferiorly and medially (Weigert-
Meyer rule) the ectopic ureter may be
stenotic and obstructed
Spot film taken during an IVP shows
bilateral duplex kidneys
On the left side the ureters have
fused at the level of L3 vertebra
On the right side both ureters have
opened into the bladder
Fluoroscopy MCU Grade 5 reflux with
double excretory system on the left side
Fusion of both ureters right before the
bladder (cystoscopy confirmed the
presence of only 2 ostia in the bladder)
Hydronephrosis
Drooping lily sign - a urographic
sign of duplicated renal
collecting system It refers to the
inferolateral displacement of
the opacified lower pole moiety
due to an obstructed (and
relatively unopacified) upper pole moiety
In duplicated collecting system
it is classically the upper pole
ureter that is obstructed due to
a ureterocoele and the lower
pole ureter that refluxes as
described by the Weigert-Meyer
law
left sided duplicated collecting system
with a distorted lower pole moiety from
obstructed upper pole This results in the
so called drooping lilly sign
Congenital ureteropelvic junction
(UPJ) obstruction
Most common congenital anomaly of the GU tract in neonates 20 of
obstructions are bilateral
bull Intrinsic 80 defect in circular muscle bundle
of renal pelvis
bull Extrinsic 20 renal vessels (lower pole artery
or vein)
The estimated incidence in pediatric population is at ~1 per 1000-2000
newborns and there is a recognised predilection towards the left side
(~67 of cases) and a male predominance
Congenital ureteropelvic junction
(UPJ) obstruction
asymptomatic or When symptomatic symptoms include recurrent urinary tract infections stone formation and even a palpable flank mass
Ultrasound
will often show a dilated renal pelvis with a collapsed proximal ureter
with Doppler sonography the obstructed kidneys can show higher RIs (resistive indices)
CT
May show evidence of hydronephrosis +- calyectasis with collapsed ureters Useful for assessing crossing vessels at the PUJ especially when surgical intervention is planned
Congenital ureteropelvic junction
(UPJ) obstruction Left sided
hydronephrosis is seen
with dilated and
ballooned out left renal
pelvis
Left pelviureteric
junction is markedly
narrowed with probably delayed contrast
excretion into left ureter
Congenital ureteropelvic junction
(UPJ) obstruction Right PUJ obstruction
Dilated renal pelvis and renal
calices with normal ureter
Congenital megacalyces
is an incidental finding which mimics hydronephrosis It is a result of
underdevelopment of the renal medullary pyramids with resultant
enlargement of the calyces It it more frequently seen in males
The enlarged floppy calyces predispose to stasis infection and
calculus formation There is an association with congenital
megaureter
due to the lack of normal medullary pyramids not only are the
calyces enlarged but they lack the normal imprint from the papillae
thus having a flat appearance
Congenital megacalyces
The renal pelvis is of normal size helping to distinguish megacalyces
from hydronephrosis
In addition to enlargement of the calyces there is often also
polycalycosis (increased number of calyces) they are crowded
and multifaceted with a mosaic-like appearance
Congenital megacalyces
This 10-month old male had a large right
kidney thought to be due to tumour
There are more than the usual number of
calyces
(PYELO)Calyceal diverticulum
Outpouching of calyx into corticomedullary region
May also arise from renal pelvis or an infundibulum
Usually asymptomatic but patients may develop calculi
bull Type I originates from minor calyx
bull Type II originates from infundibulum
bull Type III originates from renal pelvis
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Urinary bladder
rectum
prostate
Anatomy of the urinary tract
The urethra The male urethra runs from the internal urethral sphincter at the neck
of the bladder to the external urethral orifice at the tip of the penis
The posterior urethra comprises the prostatic and membranous
urethra and the anterior part comprises the bulbous and penile
urethra
In females This is 4 cm long It extends from the internal urethral
sphincter at the bladder neck through the urogenital diaphragm to
the external urethral meatus anterior to the vaginal opening
1Balloon of catheter in
navicular fossa
2 Penile urethra
3 Bulbous urethra
4 Membranous urethra
5 Impression of verumontanum in
prostatic urethra
6 Filling of utricle (not usually seen)
7 Air bubbles in
contrast
Imaging techniques of the urinary
tract
kub
Ivu
Mcug
Ultrasound
Ascending urethrogram
Mri
Pelvicalyceal system
Duplex collecting system
Congenital ureteropelvic junction (UPJ) obstruction
Congenital megacalyces
(PYELO)Calyceal diverticulum
Renal papillary necrosis (RPN)
Pyonephrosis
Duplex collecting system
It is one of the most common congenital renal tract abnormalities 4-
5 It is characterised by incomplete fusion of upper and lower pole
moieties resulting in complete or incomplete duplication of the
collecting system
duplex collecting system - a duplex kidney draining into
single ureter - ie duplex kidneys duplication pelvicalcyeal systems uniting at the pelvi-ureteric junction (PUJ)
bifid ureter (ureter fissus) - two ureters that unite before emptying into
the bladder
double ureter (complete duplication) two ureters that drain separately
into the bladder or genital tract
Duplex collecting system
Orthotopic ureter drains lower pole and
enters bladder near trigone
Ectopic ureter drains upper pole and enters
bladder inferiorly and medially (Weigert-
Meyer rule) the ectopic ureter may be
stenotic and obstructed
Spot film taken during an IVP shows
bilateral duplex kidneys
On the left side the ureters have
fused at the level of L3 vertebra
On the right side both ureters have
opened into the bladder
Fluoroscopy MCU Grade 5 reflux with
double excretory system on the left side
Fusion of both ureters right before the
bladder (cystoscopy confirmed the
presence of only 2 ostia in the bladder)
Hydronephrosis
Drooping lily sign - a urographic
sign of duplicated renal
collecting system It refers to the
inferolateral displacement of
the opacified lower pole moiety
due to an obstructed (and
relatively unopacified) upper pole moiety
In duplicated collecting system
it is classically the upper pole
ureter that is obstructed due to
a ureterocoele and the lower
pole ureter that refluxes as
described by the Weigert-Meyer
law
left sided duplicated collecting system
with a distorted lower pole moiety from
obstructed upper pole This results in the
so called drooping lilly sign
Congenital ureteropelvic junction
(UPJ) obstruction
Most common congenital anomaly of the GU tract in neonates 20 of
obstructions are bilateral
bull Intrinsic 80 defect in circular muscle bundle
of renal pelvis
bull Extrinsic 20 renal vessels (lower pole artery
or vein)
The estimated incidence in pediatric population is at ~1 per 1000-2000
newborns and there is a recognised predilection towards the left side
(~67 of cases) and a male predominance
Congenital ureteropelvic junction
(UPJ) obstruction
asymptomatic or When symptomatic symptoms include recurrent urinary tract infections stone formation and even a palpable flank mass
Ultrasound
will often show a dilated renal pelvis with a collapsed proximal ureter
with Doppler sonography the obstructed kidneys can show higher RIs (resistive indices)
CT
May show evidence of hydronephrosis +- calyectasis with collapsed ureters Useful for assessing crossing vessels at the PUJ especially when surgical intervention is planned
Congenital ureteropelvic junction
(UPJ) obstruction Left sided
hydronephrosis is seen
with dilated and
ballooned out left renal
pelvis
Left pelviureteric
junction is markedly
narrowed with probably delayed contrast
excretion into left ureter
Congenital ureteropelvic junction
(UPJ) obstruction Right PUJ obstruction
Dilated renal pelvis and renal
calices with normal ureter
Congenital megacalyces
is an incidental finding which mimics hydronephrosis It is a result of
underdevelopment of the renal medullary pyramids with resultant
enlargement of the calyces It it more frequently seen in males
The enlarged floppy calyces predispose to stasis infection and
calculus formation There is an association with congenital
megaureter
due to the lack of normal medullary pyramids not only are the
calyces enlarged but they lack the normal imprint from the papillae
thus having a flat appearance
Congenital megacalyces
The renal pelvis is of normal size helping to distinguish megacalyces
from hydronephrosis
In addition to enlargement of the calyces there is often also
polycalycosis (increased number of calyces) they are crowded
and multifaceted with a mosaic-like appearance
Congenital megacalyces
This 10-month old male had a large right
kidney thought to be due to tumour
There are more than the usual number of
calyces
(PYELO)Calyceal diverticulum
Outpouching of calyx into corticomedullary region
May also arise from renal pelvis or an infundibulum
Usually asymptomatic but patients may develop calculi
bull Type I originates from minor calyx
bull Type II originates from infundibulum
bull Type III originates from renal pelvis
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Anatomy of the urinary tract
The urethra The male urethra runs from the internal urethral sphincter at the neck
of the bladder to the external urethral orifice at the tip of the penis
The posterior urethra comprises the prostatic and membranous
urethra and the anterior part comprises the bulbous and penile
urethra
In females This is 4 cm long It extends from the internal urethral
sphincter at the bladder neck through the urogenital diaphragm to
the external urethral meatus anterior to the vaginal opening
1Balloon of catheter in
navicular fossa
2 Penile urethra
3 Bulbous urethra
4 Membranous urethra
5 Impression of verumontanum in
prostatic urethra
6 Filling of utricle (not usually seen)
7 Air bubbles in
contrast
Imaging techniques of the urinary
tract
kub
Ivu
Mcug
Ultrasound
Ascending urethrogram
Mri
Pelvicalyceal system
Duplex collecting system
Congenital ureteropelvic junction (UPJ) obstruction
Congenital megacalyces
(PYELO)Calyceal diverticulum
Renal papillary necrosis (RPN)
Pyonephrosis
Duplex collecting system
It is one of the most common congenital renal tract abnormalities 4-
5 It is characterised by incomplete fusion of upper and lower pole
moieties resulting in complete or incomplete duplication of the
collecting system
duplex collecting system - a duplex kidney draining into
single ureter - ie duplex kidneys duplication pelvicalcyeal systems uniting at the pelvi-ureteric junction (PUJ)
bifid ureter (ureter fissus) - two ureters that unite before emptying into
the bladder
double ureter (complete duplication) two ureters that drain separately
into the bladder or genital tract
Duplex collecting system
Orthotopic ureter drains lower pole and
enters bladder near trigone
Ectopic ureter drains upper pole and enters
bladder inferiorly and medially (Weigert-
Meyer rule) the ectopic ureter may be
stenotic and obstructed
Spot film taken during an IVP shows
bilateral duplex kidneys
On the left side the ureters have
fused at the level of L3 vertebra
On the right side both ureters have
opened into the bladder
Fluoroscopy MCU Grade 5 reflux with
double excretory system on the left side
Fusion of both ureters right before the
bladder (cystoscopy confirmed the
presence of only 2 ostia in the bladder)
Hydronephrosis
Drooping lily sign - a urographic
sign of duplicated renal
collecting system It refers to the
inferolateral displacement of
the opacified lower pole moiety
due to an obstructed (and
relatively unopacified) upper pole moiety
In duplicated collecting system
it is classically the upper pole
ureter that is obstructed due to
a ureterocoele and the lower
pole ureter that refluxes as
described by the Weigert-Meyer
law
left sided duplicated collecting system
with a distorted lower pole moiety from
obstructed upper pole This results in the
so called drooping lilly sign
Congenital ureteropelvic junction
(UPJ) obstruction
Most common congenital anomaly of the GU tract in neonates 20 of
obstructions are bilateral
bull Intrinsic 80 defect in circular muscle bundle
of renal pelvis
bull Extrinsic 20 renal vessels (lower pole artery
or vein)
The estimated incidence in pediatric population is at ~1 per 1000-2000
newborns and there is a recognised predilection towards the left side
(~67 of cases) and a male predominance
Congenital ureteropelvic junction
(UPJ) obstruction
asymptomatic or When symptomatic symptoms include recurrent urinary tract infections stone formation and even a palpable flank mass
Ultrasound
will often show a dilated renal pelvis with a collapsed proximal ureter
with Doppler sonography the obstructed kidneys can show higher RIs (resistive indices)
CT
May show evidence of hydronephrosis +- calyectasis with collapsed ureters Useful for assessing crossing vessels at the PUJ especially when surgical intervention is planned
Congenital ureteropelvic junction
(UPJ) obstruction Left sided
hydronephrosis is seen
with dilated and
ballooned out left renal
pelvis
Left pelviureteric
junction is markedly
narrowed with probably delayed contrast
excretion into left ureter
Congenital ureteropelvic junction
(UPJ) obstruction Right PUJ obstruction
Dilated renal pelvis and renal
calices with normal ureter
Congenital megacalyces
is an incidental finding which mimics hydronephrosis It is a result of
underdevelopment of the renal medullary pyramids with resultant
enlargement of the calyces It it more frequently seen in males
The enlarged floppy calyces predispose to stasis infection and
calculus formation There is an association with congenital
megaureter
due to the lack of normal medullary pyramids not only are the
calyces enlarged but they lack the normal imprint from the papillae
thus having a flat appearance
Congenital megacalyces
The renal pelvis is of normal size helping to distinguish megacalyces
from hydronephrosis
In addition to enlargement of the calyces there is often also
polycalycosis (increased number of calyces) they are crowded
and multifaceted with a mosaic-like appearance
Congenital megacalyces
This 10-month old male had a large right
kidney thought to be due to tumour
There are more than the usual number of
calyces
(PYELO)Calyceal diverticulum
Outpouching of calyx into corticomedullary region
May also arise from renal pelvis or an infundibulum
Usually asymptomatic but patients may develop calculi
bull Type I originates from minor calyx
bull Type II originates from infundibulum
bull Type III originates from renal pelvis
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
1Balloon of catheter in
navicular fossa
2 Penile urethra
3 Bulbous urethra
4 Membranous urethra
5 Impression of verumontanum in
prostatic urethra
6 Filling of utricle (not usually seen)
7 Air bubbles in
contrast
Imaging techniques of the urinary
tract
kub
Ivu
Mcug
Ultrasound
Ascending urethrogram
Mri
Pelvicalyceal system
Duplex collecting system
Congenital ureteropelvic junction (UPJ) obstruction
Congenital megacalyces
(PYELO)Calyceal diverticulum
Renal papillary necrosis (RPN)
Pyonephrosis
Duplex collecting system
It is one of the most common congenital renal tract abnormalities 4-
5 It is characterised by incomplete fusion of upper and lower pole
moieties resulting in complete or incomplete duplication of the
collecting system
duplex collecting system - a duplex kidney draining into
single ureter - ie duplex kidneys duplication pelvicalcyeal systems uniting at the pelvi-ureteric junction (PUJ)
bifid ureter (ureter fissus) - two ureters that unite before emptying into
the bladder
double ureter (complete duplication) two ureters that drain separately
into the bladder or genital tract
Duplex collecting system
Orthotopic ureter drains lower pole and
enters bladder near trigone
Ectopic ureter drains upper pole and enters
bladder inferiorly and medially (Weigert-
Meyer rule) the ectopic ureter may be
stenotic and obstructed
Spot film taken during an IVP shows
bilateral duplex kidneys
On the left side the ureters have
fused at the level of L3 vertebra
On the right side both ureters have
opened into the bladder
Fluoroscopy MCU Grade 5 reflux with
double excretory system on the left side
Fusion of both ureters right before the
bladder (cystoscopy confirmed the
presence of only 2 ostia in the bladder)
Hydronephrosis
Drooping lily sign - a urographic
sign of duplicated renal
collecting system It refers to the
inferolateral displacement of
the opacified lower pole moiety
due to an obstructed (and
relatively unopacified) upper pole moiety
In duplicated collecting system
it is classically the upper pole
ureter that is obstructed due to
a ureterocoele and the lower
pole ureter that refluxes as
described by the Weigert-Meyer
law
left sided duplicated collecting system
with a distorted lower pole moiety from
obstructed upper pole This results in the
so called drooping lilly sign
Congenital ureteropelvic junction
(UPJ) obstruction
Most common congenital anomaly of the GU tract in neonates 20 of
obstructions are bilateral
bull Intrinsic 80 defect in circular muscle bundle
of renal pelvis
bull Extrinsic 20 renal vessels (lower pole artery
or vein)
The estimated incidence in pediatric population is at ~1 per 1000-2000
newborns and there is a recognised predilection towards the left side
(~67 of cases) and a male predominance
Congenital ureteropelvic junction
(UPJ) obstruction
asymptomatic or When symptomatic symptoms include recurrent urinary tract infections stone formation and even a palpable flank mass
Ultrasound
will often show a dilated renal pelvis with a collapsed proximal ureter
with Doppler sonography the obstructed kidneys can show higher RIs (resistive indices)
CT
May show evidence of hydronephrosis +- calyectasis with collapsed ureters Useful for assessing crossing vessels at the PUJ especially when surgical intervention is planned
Congenital ureteropelvic junction
(UPJ) obstruction Left sided
hydronephrosis is seen
with dilated and
ballooned out left renal
pelvis
Left pelviureteric
junction is markedly
narrowed with probably delayed contrast
excretion into left ureter
Congenital ureteropelvic junction
(UPJ) obstruction Right PUJ obstruction
Dilated renal pelvis and renal
calices with normal ureter
Congenital megacalyces
is an incidental finding which mimics hydronephrosis It is a result of
underdevelopment of the renal medullary pyramids with resultant
enlargement of the calyces It it more frequently seen in males
The enlarged floppy calyces predispose to stasis infection and
calculus formation There is an association with congenital
megaureter
due to the lack of normal medullary pyramids not only are the
calyces enlarged but they lack the normal imprint from the papillae
thus having a flat appearance
Congenital megacalyces
The renal pelvis is of normal size helping to distinguish megacalyces
from hydronephrosis
In addition to enlargement of the calyces there is often also
polycalycosis (increased number of calyces) they are crowded
and multifaceted with a mosaic-like appearance
Congenital megacalyces
This 10-month old male had a large right
kidney thought to be due to tumour
There are more than the usual number of
calyces
(PYELO)Calyceal diverticulum
Outpouching of calyx into corticomedullary region
May also arise from renal pelvis or an infundibulum
Usually asymptomatic but patients may develop calculi
bull Type I originates from minor calyx
bull Type II originates from infundibulum
bull Type III originates from renal pelvis
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Imaging techniques of the urinary
tract
kub
Ivu
Mcug
Ultrasound
Ascending urethrogram
Mri
Pelvicalyceal system
Duplex collecting system
Congenital ureteropelvic junction (UPJ) obstruction
Congenital megacalyces
(PYELO)Calyceal diverticulum
Renal papillary necrosis (RPN)
Pyonephrosis
Duplex collecting system
It is one of the most common congenital renal tract abnormalities 4-
5 It is characterised by incomplete fusion of upper and lower pole
moieties resulting in complete or incomplete duplication of the
collecting system
duplex collecting system - a duplex kidney draining into
single ureter - ie duplex kidneys duplication pelvicalcyeal systems uniting at the pelvi-ureteric junction (PUJ)
bifid ureter (ureter fissus) - two ureters that unite before emptying into
the bladder
double ureter (complete duplication) two ureters that drain separately
into the bladder or genital tract
Duplex collecting system
Orthotopic ureter drains lower pole and
enters bladder near trigone
Ectopic ureter drains upper pole and enters
bladder inferiorly and medially (Weigert-
Meyer rule) the ectopic ureter may be
stenotic and obstructed
Spot film taken during an IVP shows
bilateral duplex kidneys
On the left side the ureters have
fused at the level of L3 vertebra
On the right side both ureters have
opened into the bladder
Fluoroscopy MCU Grade 5 reflux with
double excretory system on the left side
Fusion of both ureters right before the
bladder (cystoscopy confirmed the
presence of only 2 ostia in the bladder)
Hydronephrosis
Drooping lily sign - a urographic
sign of duplicated renal
collecting system It refers to the
inferolateral displacement of
the opacified lower pole moiety
due to an obstructed (and
relatively unopacified) upper pole moiety
In duplicated collecting system
it is classically the upper pole
ureter that is obstructed due to
a ureterocoele and the lower
pole ureter that refluxes as
described by the Weigert-Meyer
law
left sided duplicated collecting system
with a distorted lower pole moiety from
obstructed upper pole This results in the
so called drooping lilly sign
Congenital ureteropelvic junction
(UPJ) obstruction
Most common congenital anomaly of the GU tract in neonates 20 of
obstructions are bilateral
bull Intrinsic 80 defect in circular muscle bundle
of renal pelvis
bull Extrinsic 20 renal vessels (lower pole artery
or vein)
The estimated incidence in pediatric population is at ~1 per 1000-2000
newborns and there is a recognised predilection towards the left side
(~67 of cases) and a male predominance
Congenital ureteropelvic junction
(UPJ) obstruction
asymptomatic or When symptomatic symptoms include recurrent urinary tract infections stone formation and even a palpable flank mass
Ultrasound
will often show a dilated renal pelvis with a collapsed proximal ureter
with Doppler sonography the obstructed kidneys can show higher RIs (resistive indices)
CT
May show evidence of hydronephrosis +- calyectasis with collapsed ureters Useful for assessing crossing vessels at the PUJ especially when surgical intervention is planned
Congenital ureteropelvic junction
(UPJ) obstruction Left sided
hydronephrosis is seen
with dilated and
ballooned out left renal
pelvis
Left pelviureteric
junction is markedly
narrowed with probably delayed contrast
excretion into left ureter
Congenital ureteropelvic junction
(UPJ) obstruction Right PUJ obstruction
Dilated renal pelvis and renal
calices with normal ureter
Congenital megacalyces
is an incidental finding which mimics hydronephrosis It is a result of
underdevelopment of the renal medullary pyramids with resultant
enlargement of the calyces It it more frequently seen in males
The enlarged floppy calyces predispose to stasis infection and
calculus formation There is an association with congenital
megaureter
due to the lack of normal medullary pyramids not only are the
calyces enlarged but they lack the normal imprint from the papillae
thus having a flat appearance
Congenital megacalyces
The renal pelvis is of normal size helping to distinguish megacalyces
from hydronephrosis
In addition to enlargement of the calyces there is often also
polycalycosis (increased number of calyces) they are crowded
and multifaceted with a mosaic-like appearance
Congenital megacalyces
This 10-month old male had a large right
kidney thought to be due to tumour
There are more than the usual number of
calyces
(PYELO)Calyceal diverticulum
Outpouching of calyx into corticomedullary region
May also arise from renal pelvis or an infundibulum
Usually asymptomatic but patients may develop calculi
bull Type I originates from minor calyx
bull Type II originates from infundibulum
bull Type III originates from renal pelvis
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Pelvicalyceal system
Duplex collecting system
Congenital ureteropelvic junction (UPJ) obstruction
Congenital megacalyces
(PYELO)Calyceal diverticulum
Renal papillary necrosis (RPN)
Pyonephrosis
Duplex collecting system
It is one of the most common congenital renal tract abnormalities 4-
5 It is characterised by incomplete fusion of upper and lower pole
moieties resulting in complete or incomplete duplication of the
collecting system
duplex collecting system - a duplex kidney draining into
single ureter - ie duplex kidneys duplication pelvicalcyeal systems uniting at the pelvi-ureteric junction (PUJ)
bifid ureter (ureter fissus) - two ureters that unite before emptying into
the bladder
double ureter (complete duplication) two ureters that drain separately
into the bladder or genital tract
Duplex collecting system
Orthotopic ureter drains lower pole and
enters bladder near trigone
Ectopic ureter drains upper pole and enters
bladder inferiorly and medially (Weigert-
Meyer rule) the ectopic ureter may be
stenotic and obstructed
Spot film taken during an IVP shows
bilateral duplex kidneys
On the left side the ureters have
fused at the level of L3 vertebra
On the right side both ureters have
opened into the bladder
Fluoroscopy MCU Grade 5 reflux with
double excretory system on the left side
Fusion of both ureters right before the
bladder (cystoscopy confirmed the
presence of only 2 ostia in the bladder)
Hydronephrosis
Drooping lily sign - a urographic
sign of duplicated renal
collecting system It refers to the
inferolateral displacement of
the opacified lower pole moiety
due to an obstructed (and
relatively unopacified) upper pole moiety
In duplicated collecting system
it is classically the upper pole
ureter that is obstructed due to
a ureterocoele and the lower
pole ureter that refluxes as
described by the Weigert-Meyer
law
left sided duplicated collecting system
with a distorted lower pole moiety from
obstructed upper pole This results in the
so called drooping lilly sign
Congenital ureteropelvic junction
(UPJ) obstruction
Most common congenital anomaly of the GU tract in neonates 20 of
obstructions are bilateral
bull Intrinsic 80 defect in circular muscle bundle
of renal pelvis
bull Extrinsic 20 renal vessels (lower pole artery
or vein)
The estimated incidence in pediatric population is at ~1 per 1000-2000
newborns and there is a recognised predilection towards the left side
(~67 of cases) and a male predominance
Congenital ureteropelvic junction
(UPJ) obstruction
asymptomatic or When symptomatic symptoms include recurrent urinary tract infections stone formation and even a palpable flank mass
Ultrasound
will often show a dilated renal pelvis with a collapsed proximal ureter
with Doppler sonography the obstructed kidneys can show higher RIs (resistive indices)
CT
May show evidence of hydronephrosis +- calyectasis with collapsed ureters Useful for assessing crossing vessels at the PUJ especially when surgical intervention is planned
Congenital ureteropelvic junction
(UPJ) obstruction Left sided
hydronephrosis is seen
with dilated and
ballooned out left renal
pelvis
Left pelviureteric
junction is markedly
narrowed with probably delayed contrast
excretion into left ureter
Congenital ureteropelvic junction
(UPJ) obstruction Right PUJ obstruction
Dilated renal pelvis and renal
calices with normal ureter
Congenital megacalyces
is an incidental finding which mimics hydronephrosis It is a result of
underdevelopment of the renal medullary pyramids with resultant
enlargement of the calyces It it more frequently seen in males
The enlarged floppy calyces predispose to stasis infection and
calculus formation There is an association with congenital
megaureter
due to the lack of normal medullary pyramids not only are the
calyces enlarged but they lack the normal imprint from the papillae
thus having a flat appearance
Congenital megacalyces
The renal pelvis is of normal size helping to distinguish megacalyces
from hydronephrosis
In addition to enlargement of the calyces there is often also
polycalycosis (increased number of calyces) they are crowded
and multifaceted with a mosaic-like appearance
Congenital megacalyces
This 10-month old male had a large right
kidney thought to be due to tumour
There are more than the usual number of
calyces
(PYELO)Calyceal diverticulum
Outpouching of calyx into corticomedullary region
May also arise from renal pelvis or an infundibulum
Usually asymptomatic but patients may develop calculi
bull Type I originates from minor calyx
bull Type II originates from infundibulum
bull Type III originates from renal pelvis
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Duplex collecting system
It is one of the most common congenital renal tract abnormalities 4-
5 It is characterised by incomplete fusion of upper and lower pole
moieties resulting in complete or incomplete duplication of the
collecting system
duplex collecting system - a duplex kidney draining into
single ureter - ie duplex kidneys duplication pelvicalcyeal systems uniting at the pelvi-ureteric junction (PUJ)
bifid ureter (ureter fissus) - two ureters that unite before emptying into
the bladder
double ureter (complete duplication) two ureters that drain separately
into the bladder or genital tract
Duplex collecting system
Orthotopic ureter drains lower pole and
enters bladder near trigone
Ectopic ureter drains upper pole and enters
bladder inferiorly and medially (Weigert-
Meyer rule) the ectopic ureter may be
stenotic and obstructed
Spot film taken during an IVP shows
bilateral duplex kidneys
On the left side the ureters have
fused at the level of L3 vertebra
On the right side both ureters have
opened into the bladder
Fluoroscopy MCU Grade 5 reflux with
double excretory system on the left side
Fusion of both ureters right before the
bladder (cystoscopy confirmed the
presence of only 2 ostia in the bladder)
Hydronephrosis
Drooping lily sign - a urographic
sign of duplicated renal
collecting system It refers to the
inferolateral displacement of
the opacified lower pole moiety
due to an obstructed (and
relatively unopacified) upper pole moiety
In duplicated collecting system
it is classically the upper pole
ureter that is obstructed due to
a ureterocoele and the lower
pole ureter that refluxes as
described by the Weigert-Meyer
law
left sided duplicated collecting system
with a distorted lower pole moiety from
obstructed upper pole This results in the
so called drooping lilly sign
Congenital ureteropelvic junction
(UPJ) obstruction
Most common congenital anomaly of the GU tract in neonates 20 of
obstructions are bilateral
bull Intrinsic 80 defect in circular muscle bundle
of renal pelvis
bull Extrinsic 20 renal vessels (lower pole artery
or vein)
The estimated incidence in pediatric population is at ~1 per 1000-2000
newborns and there is a recognised predilection towards the left side
(~67 of cases) and a male predominance
Congenital ureteropelvic junction
(UPJ) obstruction
asymptomatic or When symptomatic symptoms include recurrent urinary tract infections stone formation and even a palpable flank mass
Ultrasound
will often show a dilated renal pelvis with a collapsed proximal ureter
with Doppler sonography the obstructed kidneys can show higher RIs (resistive indices)
CT
May show evidence of hydronephrosis +- calyectasis with collapsed ureters Useful for assessing crossing vessels at the PUJ especially when surgical intervention is planned
Congenital ureteropelvic junction
(UPJ) obstruction Left sided
hydronephrosis is seen
with dilated and
ballooned out left renal
pelvis
Left pelviureteric
junction is markedly
narrowed with probably delayed contrast
excretion into left ureter
Congenital ureteropelvic junction
(UPJ) obstruction Right PUJ obstruction
Dilated renal pelvis and renal
calices with normal ureter
Congenital megacalyces
is an incidental finding which mimics hydronephrosis It is a result of
underdevelopment of the renal medullary pyramids with resultant
enlargement of the calyces It it more frequently seen in males
The enlarged floppy calyces predispose to stasis infection and
calculus formation There is an association with congenital
megaureter
due to the lack of normal medullary pyramids not only are the
calyces enlarged but they lack the normal imprint from the papillae
thus having a flat appearance
Congenital megacalyces
The renal pelvis is of normal size helping to distinguish megacalyces
from hydronephrosis
In addition to enlargement of the calyces there is often also
polycalycosis (increased number of calyces) they are crowded
and multifaceted with a mosaic-like appearance
Congenital megacalyces
This 10-month old male had a large right
kidney thought to be due to tumour
There are more than the usual number of
calyces
(PYELO)Calyceal diverticulum
Outpouching of calyx into corticomedullary region
May also arise from renal pelvis or an infundibulum
Usually asymptomatic but patients may develop calculi
bull Type I originates from minor calyx
bull Type II originates from infundibulum
bull Type III originates from renal pelvis
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Duplex collecting system
Orthotopic ureter drains lower pole and
enters bladder near trigone
Ectopic ureter drains upper pole and enters
bladder inferiorly and medially (Weigert-
Meyer rule) the ectopic ureter may be
stenotic and obstructed
Spot film taken during an IVP shows
bilateral duplex kidneys
On the left side the ureters have
fused at the level of L3 vertebra
On the right side both ureters have
opened into the bladder
Fluoroscopy MCU Grade 5 reflux with
double excretory system on the left side
Fusion of both ureters right before the
bladder (cystoscopy confirmed the
presence of only 2 ostia in the bladder)
Hydronephrosis
Drooping lily sign - a urographic
sign of duplicated renal
collecting system It refers to the
inferolateral displacement of
the opacified lower pole moiety
due to an obstructed (and
relatively unopacified) upper pole moiety
In duplicated collecting system
it is classically the upper pole
ureter that is obstructed due to
a ureterocoele and the lower
pole ureter that refluxes as
described by the Weigert-Meyer
law
left sided duplicated collecting system
with a distorted lower pole moiety from
obstructed upper pole This results in the
so called drooping lilly sign
Congenital ureteropelvic junction
(UPJ) obstruction
Most common congenital anomaly of the GU tract in neonates 20 of
obstructions are bilateral
bull Intrinsic 80 defect in circular muscle bundle
of renal pelvis
bull Extrinsic 20 renal vessels (lower pole artery
or vein)
The estimated incidence in pediatric population is at ~1 per 1000-2000
newborns and there is a recognised predilection towards the left side
(~67 of cases) and a male predominance
Congenital ureteropelvic junction
(UPJ) obstruction
asymptomatic or When symptomatic symptoms include recurrent urinary tract infections stone formation and even a palpable flank mass
Ultrasound
will often show a dilated renal pelvis with a collapsed proximal ureter
with Doppler sonography the obstructed kidneys can show higher RIs (resistive indices)
CT
May show evidence of hydronephrosis +- calyectasis with collapsed ureters Useful for assessing crossing vessels at the PUJ especially when surgical intervention is planned
Congenital ureteropelvic junction
(UPJ) obstruction Left sided
hydronephrosis is seen
with dilated and
ballooned out left renal
pelvis
Left pelviureteric
junction is markedly
narrowed with probably delayed contrast
excretion into left ureter
Congenital ureteropelvic junction
(UPJ) obstruction Right PUJ obstruction
Dilated renal pelvis and renal
calices with normal ureter
Congenital megacalyces
is an incidental finding which mimics hydronephrosis It is a result of
underdevelopment of the renal medullary pyramids with resultant
enlargement of the calyces It it more frequently seen in males
The enlarged floppy calyces predispose to stasis infection and
calculus formation There is an association with congenital
megaureter
due to the lack of normal medullary pyramids not only are the
calyces enlarged but they lack the normal imprint from the papillae
thus having a flat appearance
Congenital megacalyces
The renal pelvis is of normal size helping to distinguish megacalyces
from hydronephrosis
In addition to enlargement of the calyces there is often also
polycalycosis (increased number of calyces) they are crowded
and multifaceted with a mosaic-like appearance
Congenital megacalyces
This 10-month old male had a large right
kidney thought to be due to tumour
There are more than the usual number of
calyces
(PYELO)Calyceal diverticulum
Outpouching of calyx into corticomedullary region
May also arise from renal pelvis or an infundibulum
Usually asymptomatic but patients may develop calculi
bull Type I originates from minor calyx
bull Type II originates from infundibulum
bull Type III originates from renal pelvis
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Spot film taken during an IVP shows
bilateral duplex kidneys
On the left side the ureters have
fused at the level of L3 vertebra
On the right side both ureters have
opened into the bladder
Fluoroscopy MCU Grade 5 reflux with
double excretory system on the left side
Fusion of both ureters right before the
bladder (cystoscopy confirmed the
presence of only 2 ostia in the bladder)
Hydronephrosis
Drooping lily sign - a urographic
sign of duplicated renal
collecting system It refers to the
inferolateral displacement of
the opacified lower pole moiety
due to an obstructed (and
relatively unopacified) upper pole moiety
In duplicated collecting system
it is classically the upper pole
ureter that is obstructed due to
a ureterocoele and the lower
pole ureter that refluxes as
described by the Weigert-Meyer
law
left sided duplicated collecting system
with a distorted lower pole moiety from
obstructed upper pole This results in the
so called drooping lilly sign
Congenital ureteropelvic junction
(UPJ) obstruction
Most common congenital anomaly of the GU tract in neonates 20 of
obstructions are bilateral
bull Intrinsic 80 defect in circular muscle bundle
of renal pelvis
bull Extrinsic 20 renal vessels (lower pole artery
or vein)
The estimated incidence in pediatric population is at ~1 per 1000-2000
newborns and there is a recognised predilection towards the left side
(~67 of cases) and a male predominance
Congenital ureteropelvic junction
(UPJ) obstruction
asymptomatic or When symptomatic symptoms include recurrent urinary tract infections stone formation and even a palpable flank mass
Ultrasound
will often show a dilated renal pelvis with a collapsed proximal ureter
with Doppler sonography the obstructed kidneys can show higher RIs (resistive indices)
CT
May show evidence of hydronephrosis +- calyectasis with collapsed ureters Useful for assessing crossing vessels at the PUJ especially when surgical intervention is planned
Congenital ureteropelvic junction
(UPJ) obstruction Left sided
hydronephrosis is seen
with dilated and
ballooned out left renal
pelvis
Left pelviureteric
junction is markedly
narrowed with probably delayed contrast
excretion into left ureter
Congenital ureteropelvic junction
(UPJ) obstruction Right PUJ obstruction
Dilated renal pelvis and renal
calices with normal ureter
Congenital megacalyces
is an incidental finding which mimics hydronephrosis It is a result of
underdevelopment of the renal medullary pyramids with resultant
enlargement of the calyces It it more frequently seen in males
The enlarged floppy calyces predispose to stasis infection and
calculus formation There is an association with congenital
megaureter
due to the lack of normal medullary pyramids not only are the
calyces enlarged but they lack the normal imprint from the papillae
thus having a flat appearance
Congenital megacalyces
The renal pelvis is of normal size helping to distinguish megacalyces
from hydronephrosis
In addition to enlargement of the calyces there is often also
polycalycosis (increased number of calyces) they are crowded
and multifaceted with a mosaic-like appearance
Congenital megacalyces
This 10-month old male had a large right
kidney thought to be due to tumour
There are more than the usual number of
calyces
(PYELO)Calyceal diverticulum
Outpouching of calyx into corticomedullary region
May also arise from renal pelvis or an infundibulum
Usually asymptomatic but patients may develop calculi
bull Type I originates from minor calyx
bull Type II originates from infundibulum
bull Type III originates from renal pelvis
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Fluoroscopy MCU Grade 5 reflux with
double excretory system on the left side
Fusion of both ureters right before the
bladder (cystoscopy confirmed the
presence of only 2 ostia in the bladder)
Hydronephrosis
Drooping lily sign - a urographic
sign of duplicated renal
collecting system It refers to the
inferolateral displacement of
the opacified lower pole moiety
due to an obstructed (and
relatively unopacified) upper pole moiety
In duplicated collecting system
it is classically the upper pole
ureter that is obstructed due to
a ureterocoele and the lower
pole ureter that refluxes as
described by the Weigert-Meyer
law
left sided duplicated collecting system
with a distorted lower pole moiety from
obstructed upper pole This results in the
so called drooping lilly sign
Congenital ureteropelvic junction
(UPJ) obstruction
Most common congenital anomaly of the GU tract in neonates 20 of
obstructions are bilateral
bull Intrinsic 80 defect in circular muscle bundle
of renal pelvis
bull Extrinsic 20 renal vessels (lower pole artery
or vein)
The estimated incidence in pediatric population is at ~1 per 1000-2000
newborns and there is a recognised predilection towards the left side
(~67 of cases) and a male predominance
Congenital ureteropelvic junction
(UPJ) obstruction
asymptomatic or When symptomatic symptoms include recurrent urinary tract infections stone formation and even a palpable flank mass
Ultrasound
will often show a dilated renal pelvis with a collapsed proximal ureter
with Doppler sonography the obstructed kidneys can show higher RIs (resistive indices)
CT
May show evidence of hydronephrosis +- calyectasis with collapsed ureters Useful for assessing crossing vessels at the PUJ especially when surgical intervention is planned
Congenital ureteropelvic junction
(UPJ) obstruction Left sided
hydronephrosis is seen
with dilated and
ballooned out left renal
pelvis
Left pelviureteric
junction is markedly
narrowed with probably delayed contrast
excretion into left ureter
Congenital ureteropelvic junction
(UPJ) obstruction Right PUJ obstruction
Dilated renal pelvis and renal
calices with normal ureter
Congenital megacalyces
is an incidental finding which mimics hydronephrosis It is a result of
underdevelopment of the renal medullary pyramids with resultant
enlargement of the calyces It it more frequently seen in males
The enlarged floppy calyces predispose to stasis infection and
calculus formation There is an association with congenital
megaureter
due to the lack of normal medullary pyramids not only are the
calyces enlarged but they lack the normal imprint from the papillae
thus having a flat appearance
Congenital megacalyces
The renal pelvis is of normal size helping to distinguish megacalyces
from hydronephrosis
In addition to enlargement of the calyces there is often also
polycalycosis (increased number of calyces) they are crowded
and multifaceted with a mosaic-like appearance
Congenital megacalyces
This 10-month old male had a large right
kidney thought to be due to tumour
There are more than the usual number of
calyces
(PYELO)Calyceal diverticulum
Outpouching of calyx into corticomedullary region
May also arise from renal pelvis or an infundibulum
Usually asymptomatic but patients may develop calculi
bull Type I originates from minor calyx
bull Type II originates from infundibulum
bull Type III originates from renal pelvis
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Drooping lily sign - a urographic
sign of duplicated renal
collecting system It refers to the
inferolateral displacement of
the opacified lower pole moiety
due to an obstructed (and
relatively unopacified) upper pole moiety
In duplicated collecting system
it is classically the upper pole
ureter that is obstructed due to
a ureterocoele and the lower
pole ureter that refluxes as
described by the Weigert-Meyer
law
left sided duplicated collecting system
with a distorted lower pole moiety from
obstructed upper pole This results in the
so called drooping lilly sign
Congenital ureteropelvic junction
(UPJ) obstruction
Most common congenital anomaly of the GU tract in neonates 20 of
obstructions are bilateral
bull Intrinsic 80 defect in circular muscle bundle
of renal pelvis
bull Extrinsic 20 renal vessels (lower pole artery
or vein)
The estimated incidence in pediatric population is at ~1 per 1000-2000
newborns and there is a recognised predilection towards the left side
(~67 of cases) and a male predominance
Congenital ureteropelvic junction
(UPJ) obstruction
asymptomatic or When symptomatic symptoms include recurrent urinary tract infections stone formation and even a palpable flank mass
Ultrasound
will often show a dilated renal pelvis with a collapsed proximal ureter
with Doppler sonography the obstructed kidneys can show higher RIs (resistive indices)
CT
May show evidence of hydronephrosis +- calyectasis with collapsed ureters Useful for assessing crossing vessels at the PUJ especially when surgical intervention is planned
Congenital ureteropelvic junction
(UPJ) obstruction Left sided
hydronephrosis is seen
with dilated and
ballooned out left renal
pelvis
Left pelviureteric
junction is markedly
narrowed with probably delayed contrast
excretion into left ureter
Congenital ureteropelvic junction
(UPJ) obstruction Right PUJ obstruction
Dilated renal pelvis and renal
calices with normal ureter
Congenital megacalyces
is an incidental finding which mimics hydronephrosis It is a result of
underdevelopment of the renal medullary pyramids with resultant
enlargement of the calyces It it more frequently seen in males
The enlarged floppy calyces predispose to stasis infection and
calculus formation There is an association with congenital
megaureter
due to the lack of normal medullary pyramids not only are the
calyces enlarged but they lack the normal imprint from the papillae
thus having a flat appearance
Congenital megacalyces
The renal pelvis is of normal size helping to distinguish megacalyces
from hydronephrosis
In addition to enlargement of the calyces there is often also
polycalycosis (increased number of calyces) they are crowded
and multifaceted with a mosaic-like appearance
Congenital megacalyces
This 10-month old male had a large right
kidney thought to be due to tumour
There are more than the usual number of
calyces
(PYELO)Calyceal diverticulum
Outpouching of calyx into corticomedullary region
May also arise from renal pelvis or an infundibulum
Usually asymptomatic but patients may develop calculi
bull Type I originates from minor calyx
bull Type II originates from infundibulum
bull Type III originates from renal pelvis
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
left sided duplicated collecting system
with a distorted lower pole moiety from
obstructed upper pole This results in the
so called drooping lilly sign
Congenital ureteropelvic junction
(UPJ) obstruction
Most common congenital anomaly of the GU tract in neonates 20 of
obstructions are bilateral
bull Intrinsic 80 defect in circular muscle bundle
of renal pelvis
bull Extrinsic 20 renal vessels (lower pole artery
or vein)
The estimated incidence in pediatric population is at ~1 per 1000-2000
newborns and there is a recognised predilection towards the left side
(~67 of cases) and a male predominance
Congenital ureteropelvic junction
(UPJ) obstruction
asymptomatic or When symptomatic symptoms include recurrent urinary tract infections stone formation and even a palpable flank mass
Ultrasound
will often show a dilated renal pelvis with a collapsed proximal ureter
with Doppler sonography the obstructed kidneys can show higher RIs (resistive indices)
CT
May show evidence of hydronephrosis +- calyectasis with collapsed ureters Useful for assessing crossing vessels at the PUJ especially when surgical intervention is planned
Congenital ureteropelvic junction
(UPJ) obstruction Left sided
hydronephrosis is seen
with dilated and
ballooned out left renal
pelvis
Left pelviureteric
junction is markedly
narrowed with probably delayed contrast
excretion into left ureter
Congenital ureteropelvic junction
(UPJ) obstruction Right PUJ obstruction
Dilated renal pelvis and renal
calices with normal ureter
Congenital megacalyces
is an incidental finding which mimics hydronephrosis It is a result of
underdevelopment of the renal medullary pyramids with resultant
enlargement of the calyces It it more frequently seen in males
The enlarged floppy calyces predispose to stasis infection and
calculus formation There is an association with congenital
megaureter
due to the lack of normal medullary pyramids not only are the
calyces enlarged but they lack the normal imprint from the papillae
thus having a flat appearance
Congenital megacalyces
The renal pelvis is of normal size helping to distinguish megacalyces
from hydronephrosis
In addition to enlargement of the calyces there is often also
polycalycosis (increased number of calyces) they are crowded
and multifaceted with a mosaic-like appearance
Congenital megacalyces
This 10-month old male had a large right
kidney thought to be due to tumour
There are more than the usual number of
calyces
(PYELO)Calyceal diverticulum
Outpouching of calyx into corticomedullary region
May also arise from renal pelvis or an infundibulum
Usually asymptomatic but patients may develop calculi
bull Type I originates from minor calyx
bull Type II originates from infundibulum
bull Type III originates from renal pelvis
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Congenital ureteropelvic junction
(UPJ) obstruction
Most common congenital anomaly of the GU tract in neonates 20 of
obstructions are bilateral
bull Intrinsic 80 defect in circular muscle bundle
of renal pelvis
bull Extrinsic 20 renal vessels (lower pole artery
or vein)
The estimated incidence in pediatric population is at ~1 per 1000-2000
newborns and there is a recognised predilection towards the left side
(~67 of cases) and a male predominance
Congenital ureteropelvic junction
(UPJ) obstruction
asymptomatic or When symptomatic symptoms include recurrent urinary tract infections stone formation and even a palpable flank mass
Ultrasound
will often show a dilated renal pelvis with a collapsed proximal ureter
with Doppler sonography the obstructed kidneys can show higher RIs (resistive indices)
CT
May show evidence of hydronephrosis +- calyectasis with collapsed ureters Useful for assessing crossing vessels at the PUJ especially when surgical intervention is planned
Congenital ureteropelvic junction
(UPJ) obstruction Left sided
hydronephrosis is seen
with dilated and
ballooned out left renal
pelvis
Left pelviureteric
junction is markedly
narrowed with probably delayed contrast
excretion into left ureter
Congenital ureteropelvic junction
(UPJ) obstruction Right PUJ obstruction
Dilated renal pelvis and renal
calices with normal ureter
Congenital megacalyces
is an incidental finding which mimics hydronephrosis It is a result of
underdevelopment of the renal medullary pyramids with resultant
enlargement of the calyces It it more frequently seen in males
The enlarged floppy calyces predispose to stasis infection and
calculus formation There is an association with congenital
megaureter
due to the lack of normal medullary pyramids not only are the
calyces enlarged but they lack the normal imprint from the papillae
thus having a flat appearance
Congenital megacalyces
The renal pelvis is of normal size helping to distinguish megacalyces
from hydronephrosis
In addition to enlargement of the calyces there is often also
polycalycosis (increased number of calyces) they are crowded
and multifaceted with a mosaic-like appearance
Congenital megacalyces
This 10-month old male had a large right
kidney thought to be due to tumour
There are more than the usual number of
calyces
(PYELO)Calyceal diverticulum
Outpouching of calyx into corticomedullary region
May also arise from renal pelvis or an infundibulum
Usually asymptomatic but patients may develop calculi
bull Type I originates from minor calyx
bull Type II originates from infundibulum
bull Type III originates from renal pelvis
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Congenital ureteropelvic junction
(UPJ) obstruction
asymptomatic or When symptomatic symptoms include recurrent urinary tract infections stone formation and even a palpable flank mass
Ultrasound
will often show a dilated renal pelvis with a collapsed proximal ureter
with Doppler sonography the obstructed kidneys can show higher RIs (resistive indices)
CT
May show evidence of hydronephrosis +- calyectasis with collapsed ureters Useful for assessing crossing vessels at the PUJ especially when surgical intervention is planned
Congenital ureteropelvic junction
(UPJ) obstruction Left sided
hydronephrosis is seen
with dilated and
ballooned out left renal
pelvis
Left pelviureteric
junction is markedly
narrowed with probably delayed contrast
excretion into left ureter
Congenital ureteropelvic junction
(UPJ) obstruction Right PUJ obstruction
Dilated renal pelvis and renal
calices with normal ureter
Congenital megacalyces
is an incidental finding which mimics hydronephrosis It is a result of
underdevelopment of the renal medullary pyramids with resultant
enlargement of the calyces It it more frequently seen in males
The enlarged floppy calyces predispose to stasis infection and
calculus formation There is an association with congenital
megaureter
due to the lack of normal medullary pyramids not only are the
calyces enlarged but they lack the normal imprint from the papillae
thus having a flat appearance
Congenital megacalyces
The renal pelvis is of normal size helping to distinguish megacalyces
from hydronephrosis
In addition to enlargement of the calyces there is often also
polycalycosis (increased number of calyces) they are crowded
and multifaceted with a mosaic-like appearance
Congenital megacalyces
This 10-month old male had a large right
kidney thought to be due to tumour
There are more than the usual number of
calyces
(PYELO)Calyceal diverticulum
Outpouching of calyx into corticomedullary region
May also arise from renal pelvis or an infundibulum
Usually asymptomatic but patients may develop calculi
bull Type I originates from minor calyx
bull Type II originates from infundibulum
bull Type III originates from renal pelvis
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Congenital ureteropelvic junction
(UPJ) obstruction Left sided
hydronephrosis is seen
with dilated and
ballooned out left renal
pelvis
Left pelviureteric
junction is markedly
narrowed with probably delayed contrast
excretion into left ureter
Congenital ureteropelvic junction
(UPJ) obstruction Right PUJ obstruction
Dilated renal pelvis and renal
calices with normal ureter
Congenital megacalyces
is an incidental finding which mimics hydronephrosis It is a result of
underdevelopment of the renal medullary pyramids with resultant
enlargement of the calyces It it more frequently seen in males
The enlarged floppy calyces predispose to stasis infection and
calculus formation There is an association with congenital
megaureter
due to the lack of normal medullary pyramids not only are the
calyces enlarged but they lack the normal imprint from the papillae
thus having a flat appearance
Congenital megacalyces
The renal pelvis is of normal size helping to distinguish megacalyces
from hydronephrosis
In addition to enlargement of the calyces there is often also
polycalycosis (increased number of calyces) they are crowded
and multifaceted with a mosaic-like appearance
Congenital megacalyces
This 10-month old male had a large right
kidney thought to be due to tumour
There are more than the usual number of
calyces
(PYELO)Calyceal diverticulum
Outpouching of calyx into corticomedullary region
May also arise from renal pelvis or an infundibulum
Usually asymptomatic but patients may develop calculi
bull Type I originates from minor calyx
bull Type II originates from infundibulum
bull Type III originates from renal pelvis
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Congenital ureteropelvic junction
(UPJ) obstruction Right PUJ obstruction
Dilated renal pelvis and renal
calices with normal ureter
Congenital megacalyces
is an incidental finding which mimics hydronephrosis It is a result of
underdevelopment of the renal medullary pyramids with resultant
enlargement of the calyces It it more frequently seen in males
The enlarged floppy calyces predispose to stasis infection and
calculus formation There is an association with congenital
megaureter
due to the lack of normal medullary pyramids not only are the
calyces enlarged but they lack the normal imprint from the papillae
thus having a flat appearance
Congenital megacalyces
The renal pelvis is of normal size helping to distinguish megacalyces
from hydronephrosis
In addition to enlargement of the calyces there is often also
polycalycosis (increased number of calyces) they are crowded
and multifaceted with a mosaic-like appearance
Congenital megacalyces
This 10-month old male had a large right
kidney thought to be due to tumour
There are more than the usual number of
calyces
(PYELO)Calyceal diverticulum
Outpouching of calyx into corticomedullary region
May also arise from renal pelvis or an infundibulum
Usually asymptomatic but patients may develop calculi
bull Type I originates from minor calyx
bull Type II originates from infundibulum
bull Type III originates from renal pelvis
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Congenital megacalyces
is an incidental finding which mimics hydronephrosis It is a result of
underdevelopment of the renal medullary pyramids with resultant
enlargement of the calyces It it more frequently seen in males
The enlarged floppy calyces predispose to stasis infection and
calculus formation There is an association with congenital
megaureter
due to the lack of normal medullary pyramids not only are the
calyces enlarged but they lack the normal imprint from the papillae
thus having a flat appearance
Congenital megacalyces
The renal pelvis is of normal size helping to distinguish megacalyces
from hydronephrosis
In addition to enlargement of the calyces there is often also
polycalycosis (increased number of calyces) they are crowded
and multifaceted with a mosaic-like appearance
Congenital megacalyces
This 10-month old male had a large right
kidney thought to be due to tumour
There are more than the usual number of
calyces
(PYELO)Calyceal diverticulum
Outpouching of calyx into corticomedullary region
May also arise from renal pelvis or an infundibulum
Usually asymptomatic but patients may develop calculi
bull Type I originates from minor calyx
bull Type II originates from infundibulum
bull Type III originates from renal pelvis
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Congenital megacalyces
The renal pelvis is of normal size helping to distinguish megacalyces
from hydronephrosis
In addition to enlargement of the calyces there is often also
polycalycosis (increased number of calyces) they are crowded
and multifaceted with a mosaic-like appearance
Congenital megacalyces
This 10-month old male had a large right
kidney thought to be due to tumour
There are more than the usual number of
calyces
(PYELO)Calyceal diverticulum
Outpouching of calyx into corticomedullary region
May also arise from renal pelvis or an infundibulum
Usually asymptomatic but patients may develop calculi
bull Type I originates from minor calyx
bull Type II originates from infundibulum
bull Type III originates from renal pelvis
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Congenital megacalyces
This 10-month old male had a large right
kidney thought to be due to tumour
There are more than the usual number of
calyces
(PYELO)Calyceal diverticulum
Outpouching of calyx into corticomedullary region
May also arise from renal pelvis or an infundibulum
Usually asymptomatic but patients may develop calculi
bull Type I originates from minor calyx
bull Type II originates from infundibulum
bull Type III originates from renal pelvis
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
(PYELO)Calyceal diverticulum
Outpouching of calyx into corticomedullary region
May also arise from renal pelvis or an infundibulum
Usually asymptomatic but patients may develop calculi
bull Type I originates from minor calyx
bull Type II originates from infundibulum
bull Type III originates from renal pelvis
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
(PYELO)Calyceal diverticulum
Imaging features -
Cystic lesion connects through channel with collecting
system
bull If the neck is not obstructed diverticula opacify retrograde from the
collecting system on delayed IVP films
bull May contain calculi or milk of calcium 50
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Calyceal diverticulum
with multiple stones a
Abdominal plain film
shows multiple calculi
(arrow) over the upper pole of the right kidney
On ten-minute excretory
urogram (EXU) all stones
are shown to be locate in
an upper pole calyceal
diverticulum (arrow)
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
(PYELO)Calyceal diverticulum
On Sonography a pyelocalyceal
diverticulum appears as a cystic lesion
which is difficult to distinguish from
simple renal cyst However the
presence of mobile echogenic and
dependent layering due to milk of
calcium is pathognomic of a
pyelocalyceal diverticulum
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Renal papillary necrosis (RPN)
RPN represents an ischemic coagulative necrosis involving variable amounts of pyramids and medullary papillae RPN never extends to the renal cortex
Causes
Ischemic necrosis
bull Diabetes mellitus
bull Chronic obstruction calculus
bull Sickle cell disease
bull Analgesics
Necrosis due to infections
bull TB
bull Fungal
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Renal papillary necrosis (RPN)
Imaging features
bull Enlargement (early)
bull Small collection of contrast medium extends outside the interpapillaryline in partial necrosis
bull Contrast may extend into central portion of papilla in ldquomedullary typerdquo RPN
bull Eventually contrast curves around papilla from both fornices resulting in ldquolobster-clawrdquo deformity
Sequestered sloughed papillae cause filling defects in collecting system ldquoring signrdquo
bull Tissue necrosis leads to blunted or clubbedcalyces
Multiple papillae affected in 85 Rimlike calcificationof necrotic papilla occurs
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Renal papillary necrosis (RPN)
Classical features may appear as 4
ball on tee
forniceal excavation
lobster claw
signet ring
sloughed papilla with clubbed caly
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Renal papillary necrosis (RPN)
Enlarged view of the left kidney showing central
papillary necrosis (top arrow) and marginal
excavation (bottom arrow) the pre-cursor to the
characteristic lobster claw appearance
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Renal papillary necrosis (RPN)
Coronal image of the left
kidney from a CT Urogram shows numerous irregular collections of
contrast arising
from the calyces some streak-like
densities and overall distortion of
the normal medullary-calycealanatomy
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Renal papillary necrosis (RPN)
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Renal Papillary Necrosis Ring Sign
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Pyonephrosis
Pyonephrosis is a term given to infection of the renal pelvic system
which can then subsequently get filled with pus and is then
complicated by obstruction
The diagnosis of pyonephrosis is suspected when the clinical
symptoms of fever and flank pain are combined with the radiologic
evidence of obstruction to the urinary tracts 1
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Pyonephrosis
Ultrasound
Usually shows dilatation of the pelvi-calyceal system with the following additional features-
echogenic collecting system debris - considered the most reliable
sign
fluid-fluid levels within the collecting system
incomplete (dirty) echoes of collecting system gas can be
occasionally seen
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Pyonephrosis
CT
The presence of clinical signs of infection with hydronephrosis on CT
is considered a more sensitive indicator of pyonephrosis than many
of the CT findings alone
thickening of the renal pelvic wall (gt2 mm)
parenchymal or perinephric inflammatory changes dilatation and
obstruction of the collecting system higher than usual attenuation
values of the fluid within the renal collecting system and layering of
contrast material above and anterior to the purulent fluid on
excretory studies
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Pyonephrosis
There is a calculus noted in right
renal pelvis causing gross
hydronephrosis and parenchymal
thinning
Parenchymal thickness is less than
2 mm at places
Pelvi-calyceal system shows fluid -debris levels with few tiny calculi
No air foci are noted
Parenchymal flow is preserved
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
The Ureters
Ectopic ureter
Ureterocele
Primary megaureter
Obstruction of collecting system
Ureteral injury
Ureteral tumors
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Ectopic ureter
Ureter does not insert in the normal location in the trigone of the bladder
Incidence MF = 16
Associations
bull 80 have complete ureteral duplication
bull 30 have a ureterocele (ldquocobra headrdquo appearanceon IVP)
Insertion Sites
bull Males ureter inserts ectopically into the bladdergt prostatic urethra gt seminal vesicles vas deferens ejaculatory ducts
bull Females ectopic ureter commonly empties into postsphinctericurethra vagina tubes perineum
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Ectopic ureter
Intravenous urography (IVU)
It can detect abnormal ureteral insertion and associated anomalies eg renal duplication
In complete duplex kidney and ureter the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction
Voiding cystourethrogram
Usually the ectopic ureter is associated with vesico-ureteric reflux which can detected and graded with VCUG
Ultrasound
Associations and complications such as duplex kidneys hydronephrosis andureterocoele can be also be assessed
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Ectopic ureter
A child with urinary incontinence
and recurrent urinary tract infection
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Ectopic ureter
An ectopic ureter is identified and
inserted into the posterior urethra
Associated grade III vesico-ureteric
reflux is also noted
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Ureterocele
A ureterocele refers to a herniation of the distal ureter into the bladder Two types
Simple (normal location of ureter) 25
bull Almost always occurs in adults
bull Usually also symptomatic in children
Ectopic (abnormal location of ureter) 75
bull Almost always associated with duplication
bull Unilateral 80
bull May obstruct entire urinary tract because of prolapse into the bladder neck causing bladder outlet obstruction
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Ureterocele
Radiographic Features
bull Ureterocele causes filling defect in bladder on IVP
bull Typical appearance of a cystic structure by US
bull Ureterocele may be distended collapsed or everted to represent a
diverticulum
Complications
Ureteroceles may contain calculi
May be very large (bladder outlet obstruction)
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Ureterocele
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Megaureter
Congenital megaureter is a basket-term to encompass causes of an
enlarged ureter which are intrinsic to the ureter rather than as a result
of a more distal abnormality eg bladder urethra It encompasses
obstructed primary megaureter
refluxing primary megaureter (although vesico-ureteric reflux (VUR) is
a cause of primary congenital megaureter it is usually considered
separately)
non-refluxing unobstructed primary megaureter
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Obstructive primary megaureter
Obstructive primary megaureter is related to a distal adynamic
segment with proximal dilatation and is a common cause of
obstructive uropathy in children It is analogous to oesophageal
achalasia or colonic Hirschsprung disease although lack of ganglion cells within the wall of the ureter has not been proven to be the
cause
the ureter tapers to a short segment of normal caliber or narrowed
distal ureter usually just above the vesicoureteric junction (VUJ)
The distal ureter above this narrowed segment is most dilated (similar
to achalasia)
There is associated hydronephrosis and active peristaltic waves can
be seen on ultrasound
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Refluxing primary megaureter
Refluxing primary megaureter is a result of an
abnormal vesico-ureteric junction which
impedes the normal anti-reflux mechanisms This
can be due to a short vertical intramural
segment congenital paraureteric diverticulum
ureterocoele with or without associated
duplicated collecting system etc
vesicoureteric reflux is demonstrated
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Non-refluxing unobstructed primary
megaureter
This is thought to be the most common cause of primary megaureter
in neonates and even though the vesicoureteric junction is normal
with no evidence of reflux or obstruction the ureter is enlarged The
cause for this is unknown
there is absent or only a minor degree of hydronephrosis Although
rare congenital megaureter may co-exist with congenital
megacalyces 1 making assessment of hydronephrosis more difficult
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Dilation and
elongation of both
ureters left gtgt right
Small left kidney
with pyelonephritic
scarring and
sloughed necrotic
papillae Single
pyelonephritic scar
on the right
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Primary megaureter - ldquoA 10 month child came
for the workup of recurrent UTI
Primary megaureter is diagnosed in the
absence of reflux stricture calculus or
ureterocelerdquo
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Vesicoureteral reflux (VUR)
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine
from the bladder into the upper urinary tract and is typically a
problem encountered in young children
The incidence of UTI is 8 in females and 2 in males
Reflux from the bladder into the upper urinary tract predisposes to
pyelonephritis by allowing entry of bacteria to the usually sterile
upper tract
As such the diagnosis is first suspected after a urinary tract infection
in a young child
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Vesicoureteral reflux (VUR)
Vesicoureteric reflux is in the majority of cases the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunne
MCUG
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG)
presence and grade of VUR
whether reflux occurs during micturition or during bladder filling
presence of associated anatomical anomalies
ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Vesicoureteral reflux (VUR)
bull Grade I reflux to ureter but not to kidney
bull Grade II reflux into ureter pelvis and
calyces without dilatations
bull Grade III reflux to calyces with mild
dilatationblunted fornices
bull Grade IV to calyces with moderate
dilatationobliteration of fornices
bull Grade V gross dilatation tortuous ureters
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Vesicoureteral reflux (VUR)
Voiding cystourethrogram demonstrates
reflux into both kidneys with dilatation of
the ureters and renal collecting system The
calyxes are distended and blunted The
urethra appears normal
This case illustrates typical bilateral grade V
vesicoureteric reflux
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Vesicoureteral reflux (VUR)
VCUG demonstrating
bilateral Grade III
vesicoureteral reflux
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Vesicoureteral reflux (VUR)
Pre-void contrast filled bladder
demonstrated bilateral vesico-
ureteral reflux with mildly tortuous
and moderately dilated ureters
with contrast reaching blunted
dilated calyces Findings are
keeping with bilateral type 4
vesico-ureteral reflux
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Obstruction of collecting
system
Causes
bull Calculi
bull Tumor
bull Previous surgery (ligation edema clot)
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Urolithiasis
refers to the presence of calculi anywhere along the course of the urinary tracts
The lifetime incidence of renal stones is high seen in as many as 5 of women and 12 of males
By far the most common stone is calcium oxalate however the exact distribution of stones depends on the population and associated metabolic abnormalities
calcium oxalate +- calcium phosphate ~75
struvite (triple phosphate) 15
pure calcium phosphate 5-7
uric acid 5-8
cystine 1
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Plain film
Calcium containing stones are radiopaque
calcium oxalate +- calcium phosphate
struvite (triple phosphate) - usually opaque but variable
pure calcium phosphate
Lucent stones include
uric acid
cystine
Indinavir stones
pure matrix stones
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Ct
On CT almost all stones are opaque but vary considerably in density
calcium oxalate +- calcium phosphate 400-600HU
struvite (triple phosphate) usually opaque but variable
pure calcium phosphate 400-600HU
uric acid 100-200HU
cystine opaque
Two radiolucent stones are worth mentioning 11
Indinavir stones - (anti-retroviral drug) radiolucent and usually undetectable on CT 5
pure matrix stones
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Ct
In patients with little retroperitoneal fat distinguishing a ureteric calculus from a phlebolith can be challenging Two signs have been found helpful 12
comet-tail sign - favours a phlebolith
soft-tissue rim sign - favours a ureteric calculus
comet-tail sign The sign refers to a tail of soft tissue extending from a calcification representing the collapsedscarredthrombosed parent vein When well seen it is said to have a positive predictive value of 100 1
The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall Phleboliths on the other hand usually have imperceptible walls (although up to 8 may have a soft tissue rim sign 2) but may have a comet-tail sign
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Ct
Findings of ureteral obstruction include
( 1 ) mild dilatation of the pelvicalyceal system and ureter (3 mm)
proximal to the stone
( 2 ) slight decrease in attenuation of the affected kidney caused by
edema
( 3 ) perinephric soft tissue stranding representing edema in the
perinephric and periureteral fat
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Nonenhanced CT image shows an
obstructing left proximal ureteral
calculus with a slight soft-tissue rim
around the stone (ie rim sign)
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
40 Male patient complaining
of right renal colic with
hematuria
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
An oval shaped radiodense
stone is seen at the junction
between upper 23 and lower
13 of the right ureter measuring
about 05 x 1 cm along its
maximum diameters and eliciting
density of about (690 HU)
associated with marked dilatation of the right pelvi-
calyceal system and proximal
part of the right ureter
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
IVP (30-minute delay image) of the right kidney shows a moderately hydronephrotic collecting system to the
level of a proximal ureteral stone (arrow) Source emedicine
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
13 minutes after infusion of contrast
medium there is contrast of the right
pyelon and in the bladder but yet no
contrast of the left pyelon There is
also contrast outlining the left kidney
whereas it has already cleared from
the right (delayed nephrogram)
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Two hours after infusion you can appreciate a
distension of the left ureter and a
hydronephrosis of the left pyelon
This examination demonstrates the typical IVP
features of collecting system dilatation and a
delayed nephrogram secondary to a distal
obstructing calculus In this case the calculus is
well seen radiographically
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
30 year old male right flank
pain ultrasound shows proximal
hydroureter and mild
hydronephrosis
Scout- apparently normal with
no evidence of calculus
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
10 min film- right sided proximal
hydroureter and mild dilatation of
pelvicalyceal system
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
15 min film- findings are persistent and
a filling defect is noted at the L3-L4
level
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Ultrasound
Ultrasound is frequently the first investigation of the renal tract and
although by no means as sensitive as CT it is often able to identify
calculi Small stones and those close to the corticomedullary
junction can be difficult to reliably identify Ultrasound compared to CT-KUB reference showed a sensitivity of only 24 in identifying
calculi Nearly three-quarters of calculi not visualised were 3mm or
less in size13 Features include 7
echogenic foci
acoustic shadowing
twinkle artefact on color Doppler
color comet-tail artefact 9
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
80 year old female Non
specific flank pain
Limited history due
patients confusion
Right hydronephrosis
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Left ureteric jet present (ie
left ureter non obstructed)
No ureteric jet on the right
(suspicious although not in itself diagnostic for ureteric
obstruction)
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Shadowing calculus at the
right VUJ
Comet tail artefact supports
the presence of a calculus
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Ureteral tumors
Types
Benign tumors
bull Epithelial inverted papilloma polyp adenoma
bull Mesodermal fibroma hemangioma myoma lymphangioma
bull Fibroepithelial polyp mobile long intraluminal mass ureteral intussusception
Malignant tumors
bull Epithelial transitional cell carcinoma SCC
adenocarcinoma
bull Mesodermal sarcoma angiosarcoma
carcinosarcoma
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Ureteral tumors
Due to the small caliber of the ureter tumours are more likely to
obstruct the kidney at small tumour size
Obstruction may lead to hyrdonephrosis with or without hydroureter
and may also result in a non-functioning kidney or delayed
nephrogram
bull Bergmans coiled catheter sign on retrograde pyelogram the
catheter is typically coiled in dilated portion of ureter just distal to the
lesion
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Ureteral tumors
Smaller or polypoid tumours may be seen as filling
defects and if they cause partial long-standing
obstruction may result in focal dilatation of the
ureter at the site of the tumour This may lead to
the so-called goblet sign best seen on
retrograde ureterography 2
Occasionally circumferential thickening of the ureteric wall results from diffuse infiltration an may
have an apple core appearance 4
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Ureteral tumors
Prognosis
bull 50 of patients will develop bladder cancer
bull 75 of tumors are unilateral
bull 5 of patients with bladder cancer will develop ureteral cancer
Sites of metastatic spread of primary ureteral neoplasm
bull Retroperitoneal lymph nodes 75
bull Liver 60
bull Lung 60
bull Bone 40
bull Gastrointestinal tract 20
bull Peritoneum 20
bull Other (lt15) adrenal glands ovary uterus
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Ureteral tumors
CT demonstrates a very large
right sided ureteric mass with
trapped contrast which almost
mimics a vascular aneurysm and
proximal long
standing hydronephrosis
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Ureteric injury
Ureteric injury is a relatively uncommon but serious event which may result in serious complications as diagnosis is often delayed
Ureteric injuries unreliably demonstrate macro- or micro-scopichaematuria as it may be absent in up to 25 of patients
There is a wide-range of injury
injury to the mucosa of the ureter post lithotripsy
perforation and false passage
partial or complete ureteric transection
complete ureteric avulsion
loss of ureteric segment
ligation
dissection
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Ureteric injury
Iatrogenic(most commonly injured after gynaecological procedures)
Traumatic
Classification
Ureteric injury can be classified into three types according to its site
upper-third
upper-third and pelvico-ureteric junction (PUJ) most affected by blunt trauma 5 7
mid-third
distal-third
most common site
often following iatrogenic injury
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Ureteric injury
Fluoroscopy
Excretory intravenous urography if CT is not available demonstrates
contrast leakage and spillage outside the course of the urinary
system
Retrograde pyelography may be performed if both
excretory intravenous urographyand CT with intravenous
contrast are inconclusive and there is still a high suspicion of injury 1
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Ureteric injury
CT
CT with intravenous contrast and delayed scan with full reformatted
sagittal and coronal images and 3D reconstruction The delayed
scan should be performed between 5-8 minutes after IV contrast to
ensure a CT-IVU (aka excretory phase) set of images is acquired
intra-abdominal fluid collections without other cause shown
contrast extravasation from renal hilumPUJ (usually medially)
without associated renal injury
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Ureteric injury
Post emergency caesarean section
intraperitoneal tube drainage high
output
Contrast leakage and spillage is seen in
the left side of pelvis in the region of lower
third left ureter denoting a left ureteric
injury
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Bladder
Bladder exstrophy
Bladder diverticulum
Bacterial cystitis
Emphysematous cystitis
Neurogenic bladder
Bladder calculi
Malignant bladder neoplasm
Bladder injuries
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Bladder exstrophy
Bladder exstrophy (also known as ectopia vesicae) refers to a herniation of the urinary bladder through an anterior abdominal wall defect The severity of these defects is widely variable
The estimated incidence of bladder exstrophy is 110000-50000 live births
It is thought to be caused by a developmental defect of the cloacal membrane which results in a subsequent eversion of the bladder mucosa This then protrudes out like the mass like lesion
General associations
extension of the bladder defect into the urethra
cryptorchidism
bilateral inguinal herniation
OEIS complex
epispadia
vaginal duplication
clitoral cleft
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Bladder exstrophy
Imaging findings include a soft-tissue mass extending from a large
infra-umbilical anterior wall defect which may be close to the
umbilical arterial exits
The absence of a normal urinary bladder and a low-lying umbilical
cord insertion may also indicate the diagnosis
Failure of the pubic bones to meet in the midline (widened pubic
symphysis) This appearance on AP plain radiograph of the pelvis
has been likened to a manta ray swimming towards you (manta ray
sign)
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Bladder exstrophy
Marked widening of the pubic
symphysis (manta ray
appearance) consistent with
bladder exstrophy for which the
patient had a known history
In terms of a cause for hip pain
there is no fracture identified but
there is mild left hip degenerative disease and mild
bilateral greater tuberosity
irregularity suggesting chronic
gluteal tendinosis
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Bladder exstrophy
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Bladder diverticulum
Bladder diverticulum are outpouchings from the bladder wall
whereby mucosa herniates through the bladder wall
They may be solitary or multiple in nature and can very considerably
in size
Diverticulae may be congenital or acquired A range of causes of
urinary bladder diverticula are described
Acquired diverticula are more common usually occurring the
context of a trabeculated bladder resulting from chronic bladder outlet obstruction
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Bladder diverticulum
Diverticula are often an incidental finding on imaging investigations
including ultrasound CT MRI and IVU
They may be associated with a range of complications including
infection
reflux
stone formation
malignancy
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Bladder diverticulum
IVU images shows a diverticulum
at the right lateral wall
Note the elevated base of the
bladder due to the enlarged
prostate
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Bladder diverticulum
Congenital diverticulae are
solitary and are most often
discovered during childhood
Acquired bladder diverticulae
are the result obstruction of the
bladder outlet or bladder
dysfunction They are often
multiple and typically seen in older men
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Bacterial cystitis
Acute Cystitis
Pathogens E coli gt Staphylococcus gt Streptococcus
gt Pseudomonas
Predisposing Factors
bull Instrumentation trauma
bull Bladder outlet obstruction neurogenic bladder
bull Calculus
bull Cystitis
bull Tumor
Imaging Features
bull Mucosal thickening (cobblestone appearance)
bull Reduced bladder capacity
bull Stranding of perivesical fat
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Emphysematous cystitis
Emphysematous cystitis refers to gas forming infection of the bladder wall
Risk factors include
female sex reported MF ratio 12
immunocompromised state
diabetes mellitus may be present in ~50 of cases 2
neurogenic bladder
transplant recipients
The most common causative organism is E coli with other organisms including Enterobacter aerogenes Klebsiellapneumonia Proteus mirabilis Staphylococcus aureus
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Emphysematous cystitis
CT
CT is a highly sensitive examination that allows early detection of
intraluminal or intramural gas
CT is also useful in evaluating other causes of intraluminal gas such
as enteric fistula formation from adjacent bowel carcinoma or
inflammatory disease
Ultrasound
Can demonstrate echogenic air within the bladder wall with dirty
shadowing artefact
Ultrasound will also commonly demonstrate diffuse bladder wall
thickening and increased echogenicity
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Emphysematous cystitis
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Neurogenic bladder
Term applied to a dysfunctional urinary bladder that results from an
injury to the central or peripheral nerves that control and regulate
urination
Injury to the brain brainstem spinal cord or peripheral nerves from
various causes including infection trauma malignancy or vascular
insult can result in a dysfunctional bladder 3
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Neurogenic bladder
In a large cohort study the mean age of neurogenic bladder
patients was 625 years and resultant etiologies included 4
multiple sclerosis ~17
Parkinson disease ~15
cauda equina syndrome ~9
paralytic syndrome ~8
stroke complications ~6
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Neurogenic bladder
A number of classification schemes exist for neurogenic bladders
including the Lapides classification which remains popular
sensory neurogenic bladder posterior columns of the spinal cord or
afferent tracts leading from the bladder
motor paralytic bladder damage to motor neurons of the bladder
uninhibited neurogenic bladder incomplete spinal cord lesions
above S2 or cerebral cortex or cerebropontine axis lesions
reflex neurogenic bladder complete spinal cord lesions above S2 -
may lead to pine cone bladder
autonomous neurogenic bladder conus or cauda equina lesions
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Neurogenic bladder
uoroscopicIVP
Sensory neurogenic bladder
Inability to sense bladder fullness results in a large rounded and smooth bladder Voiding is often preserved
Motor paralytic bladder
Atonic large bladder with inability of detrusor contraction during voiding
Unhibited neurogenic bladder
Rounded bladder with a trabeculated apperance to the mucosa above the trigone from detrusor contractions On voiding large interureteric ridge is noted
Reflex neurogenic bladder
Results from detrusor hyperreflexia with a dyssynergic sphincter This leads to contrast extension to the posterior urethra and an elongated pointed urthera with pseudodverticula
Autonomous neurogenic bladder
Intermediate between detrusor hyperreflexia (contracted) and dysreflexia (atonic)
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Neurogenic bladder
Ultrasound
Detailed images of the bladder often demonstrate a thick wall with
a small contracted or large atonic bladder
A large post void residual is often noted
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Neurogenic bladder
VCUR examination
demonstrate elongated
distended urinary bladder with
multiple urinary bladder
diverticulae characteristic of
neurogenic bladder
Grade III VUR on the left side is
also demonstrated
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Neurogenic bladder Neurogenic bladder typically occurs in
those with sacral abnormalities at birth
The appearances has been described as
a Christmas tree of pine cone bladder
The shape of the bladder is highly
abnormality with an elongated appearance with the dome like the top of
a Christmas tree
The associated bladder wall hypertrophy
gives an outline which mimics the
decorations that adorn a Christmas tree
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Neurogenic bladder
A pine cone bladder or christmas tree bladder is a cystogram appearance in which the bladder is elongated and pointed with thickened trabeculatedwall
It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesions (above S2-S4) or epiconal lesions (in and around S2-S4)
It is however not pathognomonic of a neurogenic bladder and can be seen in patients with lesions anywhere along the sacral reflex arc leading to poor detrusor compliance Occasionally it is also seen in bladder neck obstruction of a non-neurogenic cause
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Bladder calculi
Bladder calculi occur either from migrated renal calculi or urinary
stasis
Bladder calculi can be divided into primary and secondary stones
primary stones form de novo in the bladder
secondary stones are either from renal calculi which have migrated
down into the bladder or from concretions on foreign material (eg
urinary catheters)
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Bladder calculi
associated with -
bladder outlet obstruction
cystocoele
neurogenic bladder
foreign body
Radiographic features
Plain Film
Usually densely radio-opaque calculi may be single or multiple and often large Frequently lamination is observed internally like the skin of an onion
Ultrasound
Sonographically they are mobile echogenic and shadow distally
They may be associated with bladder wall thickening due to inflammation
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Bladder calculi
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Malignant bladder neoplasmClinical Finding
bull Painless hematuria
Types and Underlying Causes
Transitional cell carcinoma 90
bull Aniline dyes
bull Phenacetin
bull Pelvic radiation
bull Tobacco
bull Interstitial nephritis
SCC 5
bull Calculi
bull Chronic infection leukoplakia
bull Schistosomiasis
Adenocarcinoma 2
bull Bladder exstrophy
bull Urachal remnant
bull Cystitis glandularis 10 pass mucus
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Malignant bladder neoplasm
Ct
bladder transitional cell carcinomas appear as either focal regions of thickening of the bladder wall or as masses protruding into the bladder lumen or in advanced cases extending into adjacent tissues
The masses are of soft tissue attenuation and may be encrusted with small calcifications
MRI
MRI is superior to other modalities in locally staging the tumour and is in some instances able to distinguish T1 from T2 tumours on T2 weighted image
T1 isointense compared to muscle 4
T2 slightly hyperintense compared to muscle
T1 C+ (Gd) shows enhancement
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Polypoidal enhancing filling
defect arising from the left
bladder wall is typical of
transitional cell cancer No
obstruction to the left ureteric
orifice nor invasion through the
bladder wall
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Malignant bladder neoplasm
Mural broad-based lesion lining the left aspect of
Bladder The lesion shows
internal flow on Doppler
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Malignant bladder neoplasm
Polypoidal irregular mural thickening of the left lateral and posterior wall of the urinary bladder which coalesce to form large fungating mass arising from left lateral wall are seen and extends through the wall to invade the perivesical fat
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Bladder injuries
Extraperitoneal bladder rupture
Extraperitoneal rupture is the most common type of bladder injury accounting for ~85 (range 80-90) of cases
It is usually the result of pelvic fractures or penetrating trauma
Cystography reveals a variable path of extravasated contrast material
Intraperitoneal bladder rupture
Occurs in approximately ~15 (range 10-20) of major bladder injuries and typically is the result of a direct blow to the already distended bladder
Cystography demonstrates intraperitoneal contrast material around bowel loops between mesenteric folds and in the paracolic gutters
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Bladder injuries
Classification of Bladder Injury
bull Type 1 Bladder contusion
bull Type 2 Intraperitoneal rupture
bull Type 3 Interstitial bladder injury
bull Type 4 Extraperitoneal rupture
bull Type 4a Simple extraperitoneal rupture
bull Type 4b Complex extraperitoneal rupture
bull Type 5 Combined bladder injury
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Bladder injuries
CT
Bladder rupture is one form of genitourinary tract trauma along with
renal trauma and urethral injuries
Contrast enhanced CT is the imaging technique of choice for
bladder injuries in the form of CT cystography
This may be combined with standard CT to evauluate the upper
tracts
Standard cystography has a more limited role
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Bladder injuries
Bladder catheter balloon in the intraperitoneal space
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Bladder injuries
Postvoid film shows a flame-
shaped density adjacent to lateral
walls of bladder representing
extra-peritoneal contrast from a
bladder rupture
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
The Urethra
Posterior urethral valves (PUVs)
Urethral injuries
Urethral strictures
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Posterior urethral valves (PUVs)
Posterior urethral valves (PUVs) are the most common congenital
obstructive lesion of the urethra and a common cause of
obstructive uropathy in infancy
Posterior urethral valves are congenital and only seen in male
infants 2 The estimated incidence is at ~1 in 10000-25000 live births
with a higher rate of incidence in utero
Clinical presentation depends on the severity of obstruction In
severe obstruction the diagnosis is usually made antenatally
The fetus will be small for gestational age and ultrasound
examination will demonstrate oligohydramnios
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Posterior urethral valves (PUVs)
Associations
Posterior urethral valves are also seen in association with other
congenital abnormalities including
chromosomal abnormalities eg Down syndrome 5
bowel atresia
craniospinal defects
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Posterior urethral valves (PUVs)
UltrasoundAntenatal ultrasound
On antenatal ultrasound the appearance is that of marked distention and hypertrophy of the bladder with or without hydronephrosis and hydroureter and depending on the severity oligohydramnios and renal dysplasia
Postnatal ultrasound
The bladder is typically thick-walled and trabeculated with an elongated and dilated posterior urethra (keyhole sign)
The kidneys in most cases are hydronephrotic although it is important to note that in up to 10 of cases they appear normal 5 They may also be hyperechoic with loss of the normal corticomedullary differentiation a manifestation of renal dysplasia 5
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Posterior urethral valves (PUVs)
Voiding cystourethrogram
Voiding cystourethrogram (VCUG) is the best imaging technique for the diagnosis of posterior urethral valves
The diagnosis is best made during the micturition phase in a lateral or oblique views such that the posterior urethra can be imaged adequately
Findings include
dilatation and elongation of the posterior urethra (equivalent of the ultrasonographic keyhole sign)
linear radiolucent band corresponding to the valve (only occasionally seen)
vesicoureteral reflux (VUR) seen in 50 of patients
bladder trabeculationdiverticula
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Posterior urethral valves (PUVs)
Keyhole sign Rotated image of an
antenatal ultrasound of the foetal
pelvis demonstrating the keyhole
sign created by the distend
bladder and posterior urethra
The keyhole sign is an
ultrasonograhic sign seen in boys
with posterior urethral valves It
refers to the appearance of
posterior urethra which is dilated
and associated thick walled
distended bladder which on
ultrasound may resemble a key
hole
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Posterior urethral valves (PUVs)
Micturating
cystourethrogram reveals
marked dilatation of the
prostatic portion of the
urethra consistent with
posterior urethral valves
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Posterior urethral valves (PUVs)
Ultrasound reveals marked bilateral hydronephrosis
and hydroureter There is dependent echogenic
debris seen throughout the renal collecting system
consistent with infection
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Urethral injuries
Urethral injuries can result in long-term morbidity and most
commonly result from trauma
The male urethra is much more commonly injured than the female
urethra
Clinically blood of the external urethral meatus or vaginal introitus
may be seen but is an unreliable sign
Male urethral injuries are divided into anterior (penilebulbar) and
posterior (membranousprostatic) urethral injuries
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Urethral injuries
Classification
blunt trauma due to shearing or straddle injuries associated with
pelvic fractures (occurs in ~10) often associated with bladder
injury
penetrating trauma eg stab wounds gunshot wounds dog bites
(more commonly affect the anterior urethra)
iatrogenic for example urethral instrumentation eg
catheterisation Foley catheter removal without balloon deflation
cystoscopypost-surgical (eg surgery for benign prostatic
hyperplasia)
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Urethral injuries
Fluoroscopy
Retrograde urethrography is the modality of choice
It will demonstrate extraluminal contrast which has extravasated from the urethra
CT
CT cystography can be performed but this is much less specific for urethral vs bladder injury
Other features of urethral injury include retropubic and perivesicalhaematoma and obscuration of the urogenital fat plane
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Urethral injuries
Retrograde urethrogram in
a patient with pelvic
fractures demonstrates
contained contrast leakage
at the posterior urethra
(membranous portion)
Contrast does ascend into
the bladder and therefore the urethral injury is
incomplete
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Urethral injuries
there is a small amount of
extravasated contrast (from
prior urethrogram) within the
retro-pubic space (cave of
Retzius) inferior
extraperitoneal pelvic cavity
and tracking into the
perineumperineal muscles and adductor musculature of
the left thigh
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Urethral stricture
Clinical presentation
poor urine stream
Aetiology
Infection(gonococcal urethritis (more common))
trauma
straddle injury (most common)
pelvic fractures
iatrogenic
instrumentation
prolonged catheterisation
transurethral resection of the prostate
open radical prostatectomy
urethra reconstruction (hypospadiaepispadia)
congenital
uncommon
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Urethral stricture
Past history of
chlamyida infection
20mm stricture in the
bulbous urethra
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Urethral stricture
Short segment (5mm) stricture at
the junction of the penile and
bulbous urethra
Filling defect related to
lubricant jelly used
Thank You
Thank You