DM
Diagnostic Medical ImagingDonald Ly, Vincent Spano and Christian
'9aD der Pol, chapter editors Christophel' Kitamura and Michelle
Lam, associate editors Janine Hutson, EBM editor Dr. TaeBoog Chong,
Dr. Marc Freeman, Dr. Nasir Jaffer, Dr. Vlkram Prabhudesai and Dr.
Eugene Yu, staff editorsImaging Modalities ...................... 2
X-Ray Imaging Ultrasound (U/S) Magnetic Resonance Imaging (MRI)
Positron Emission Tomography Scans (PET) Contrast Enhancement Chest
Imaging .......................... 4 Chest X-Ray (CXR) Computed
Tomography (CT) Chest lung Abnormalities Pulmonary Vascular
Abnormalities Pleural Abnormalities Mediastinal Abnormalities
Tubes, lines, and Catheters Gastrointestinal (GI) Tract . . 11
Modalities Approach to Abdominal X-Ray (AXR) Approach to Abdominal
Computed Tomography (CT) Contrast Studies Specific Visceral Organ
Imaging "itis" Imaging Angiography of Gl Tract Genitourinary System
................... 15 Modalities Gynecological Imaging Selected
Pathology Neuroradiology . . . . . . . . . . . . . . . . . . . . .
. . . 17 Modalities Approach to CT Head Selected Pathology
Musculoskeletal System (MSK) . 20 Modalities Approach to
Interpretation of Bone X-Rays Trauma Arthritis Bone Tumour
Infection Metabolic Bone Disease Nuclear Medicine
....................... 25 Thyroid Respiratory Cardiac Bone Abdomen
Inflammation and Infection Brain lnterventional Radiology
................. 27 Vascular Procedures Nonvascular Interventions
Women's Imaging ...................... 29 Modalities Breast Imaging
Reporting Breast Findings References . . . . . . . . . . . . . . .
. . . . . . . . . . . . . 32
Please see the Essentials of Medical Imaging software for
illustration& of the content in this chapter Toronto Notes 2011
Diagnostic Medical Imaging DMI
DM2 Diagnostic Medic:allmaging
Imaging Modalities
Toronto Notes 2011
Imaging ModalitiesX-Ray ImagingDlapolllc ,....lc.. Uposartll(in
dulls)
... .,.., 1211111
D - hill
&jlillllll . . . . . .
Pnd If Nlllnl
llilllian''
lldrpnll
x-rays, or Roentgen rays, are a form of electromagnetic energy
of short wavelength as x-ray photons traverse matter, they can be
absorbed (process known as "attenuation&) and/or scattered the
density of a structure determines its ability to attenuate or
"weaken& the x-ray beam air < fat < water < bone <
metal structures that have high attenuation, e.g. bone, appear
white on the resulting images two broad categories: plain films and
computed tomography (CT)
Plain Films x-rays pass through the patient and interact with a
detection device to produce a 2-dimensional projection image
structures closer to the film appear sharper and less magnified
contraindications: pregnancy (relative) advantages: inexpensive,
non-invasive, readily available di1advantages: radiation exposure,
generally poor at distinguishing soft tissues
10 Thcnck:'line 50 75 Urrillr11Jinl Dlest PA film) I
c.Mail.SklJ
5
12d111 3WIIb 2dlys Idly 7WIIb10Mib
lateral decubitus Position
1 o
"-
Figura 1. CXR Viaws
'IbroDlo Nota 2011
Chen ImagiDg
Diagnostic Medkal I:maginB DMS
.,u
legendlllrtic arch IIGfb)iJulmanary window llllarior 8DpiiC8
carill c:lavicle CDatDplnnic qledillplnQm
12&I
llllarior 1II rib llllarior 2nd rll
apw
caclCD CPI
C11111Caid process
di g
M:Ia
lbr lpalvmi p3 p4 PIIll
mf
gllllric llubble infwior 'II'WII Cll\'& left abium lift
nw*1stam bronctus IIIII pulmarwy lrlely lift vantricla major
fissurap.,.riar 3ld rll p.,.riar 4th rll main iiUmanary artery
rightalli1.111 right maillltem bronchus rightidnanary artery right
vanlliclaSCBpWI
minur&.u11
rtJrrpll
rvIC
liP
st
Vllw
Llllaral Villw
svc1r
ll!linDUJ prDCAI stamum
superior- CIMI verblbnll bodyhehell
vb
Figura Z. Locatio of
MadiMiiul Structures and Bony l.andarks Tbla 1 Localizlllion
Uaing th Silllauatta Sign
ANATOMY
Localizing Lesions silhouette lip: loss of normal interfaces due
to lung pathology (consolidation, atelectasis, mass), which can be
used to localize disease in specific lung segments note that
pleural or mediastinal disease can also prodw::e the silhouette
signAPPROACH TO CXRBasics ID: patient name, MRN, sex. age
s.nar VIlli Cftll8/ IIUL right ..,eriar lllldiastin1111 Right
h..t bl:l'der RML Right hrllliliaiM!Jn RUAoltic knr.b' WL 18ft
si4)111iar mediaslillm
date ofexam marken: Rand/or L technique: view (e.g. PA, AP,
lateml), supine or erect
indications fur the !tudy comparison: date ofprevious study for
comparison (ifavallable) quality of film: Inspiration. penetration
and rotation
l.aft h111rt border 1.a1t hamdii!IDIIIm
l.ir;lula UL
Analysis tuba and llnet; chec::k position and be alert fur
pneumothorax or pneumomediastinum soft tiJaaes: neck, axillae,
pectoral muscles, breasts/nipples, chest wall nipple markers can
help identify nipples (may mimic lung nodules) amount ofsoft
tissue, presence of maases and air (subcutaneous emphysema) abdomen
(see GI imaging. DMll): free air under the diaphragm air fluid
levels, dlstentl.on in small and large bowels herniation
ofabdominal contents bona: C-spine, thoracic spine, shoulders,
ribs, sternum lytic and blastic lesions and fractures mediastinuln;
trachea, heart, great vessels, mediastinum, spine cardia.c
enlargement, tra.chea.l shift, tortuous aorta. widened mediastinum
Iilla: pulmonary vessels, mainstem and segmental bronchi, lymph
nodes lunp lung parenchyma. pleura. diaphragm lungs on lateral film
should become darker when going Inferiorly over the spine comment
on abnormal lung opacity, pleural effusions or thickening right
hemidlapluagm usually hlgher than left due to liver right vs.left
hemidiaphragm can be discerned on lateral CXR due to heart resting
directly on left hcmidiaphragm
C'-1 . . _ lwl*ilfllliula.iGa ABCDEF AP, PA ur ath viaw
BDC!v IIIIIB
Conm1l IBIII
lim; fur I:GIIII)IrilonAlllp.. ABCDEF Anvays.lnd hil
Adenopathy
Banesand Breast shadows Clnliac lilhau8lt8 and
llillptngm end Digutiye lriCt Edges of llleurt
...
Fields {llrlg fieldll
DM6 Diagnostic Medical Imaging
Chest Imaging
Toronto Notes 2011
RUL RML RLL FrontAP Right-Lateral
LLL
LUL LLL
"'
BackAP
Left-Lateral
Il@
RUL: Right Upper Lobe; RML: Right Middle Lobe; RLL: Right Lower
Lobe; LUL: Left Upper Lobe; LLL: Left Lower Lobe Figure 3. Location
of Lobes of the Lung
Computed Tomography (CT) ChestAPPROACH TO CT CHEST lung window
central-trachea: patency, secretions bronchial trees: anatomic
variants, mucus plugs, airway collapse lung parenchyma: fissures,
nodules bone window look at vertebrae, sternum, manubrium, ribs for
fractures, lytic lesions, sclerosis soft tissue window thyroid,
chest wall, pleura heart: chambers, coronary artery calcifications,
pericardium vessels: aorta, pulmonary artery, smaller vasculature
lymph nodes: mediastinal, axillary TYPES OF CT CHESTTable 4. Types
of CT Chest Standard Advantage Scans full lung very quickly (< 1
minute} High Resolution Thinner slices provide high definition of
lung parenchyma Only 5-1 0% lung is sampled No Hemoptysis Diffuse
lung disease (e.g. sarcoidosis, hypersensitivity pneumonitis,
pneumoconiosis} Pulmonary fibrosis Nonnal CXR but abnonnal PFTs
Characterize solitary pulmonary nodule Low Dose 1/5th the radiation
Decreased detail No
CT AngiographyIodinated contrast highlights vasculature Contrast
can cause severe allergic reaction and is nephrotoxic Yes
Disadvantage Poor at evaluating diffuse disease Contrast
Indication Figure 4. CT Thorax Windows CXR abnonnality Pleural and
mediastinal abnormality Lung cancer staging Follow up metastases
Empyema vs. abscess
Screening Pulmonary embolism Follow up infections, Aortic
aneurysms lung transplant, Aortic dissection metastases
....._'
DDx of Airspace Disease Pus (e.g. pneumonia) Fluid (e.g.
pulmonary edema) Blood (e.g. pulmonary hemorrhage) Cells (e.g.
bronchioalveolar carcinoma; lymphoma) Protein (e.g. alveolar
proteinosis)
.
, .-------------------,
Lung AbnormalitiesATELECTASIS pathophysiology: collapse of
alveoli due to restricted breathing, blockage of bronchi, external
compression or poor surfactant signs increased opacity of involved
segment/lobe, silhouette sign volume loss: fissure deviation,
hilar/mediastinal displacement, diaphragm elevation vascular
crowding compensatory hyperinflation of remaining normal lung air
bronchograms (also seen in consolidation) differential obstructive
(most common}: air distal to obstruction is reabsorbed causing
alveolar collapse endobronchial lesion, foreign body, inflammation
(granulomatous infections, pneumoconiosis, sarcoidosis, radiation
injury} or mucous plug (seen in cystic fibrosis) compressive
tumour, bulla, effusion, enlarged heart, lymphadenopathy traction
(cicatrization}: due to scarring, which distorts alveoli and
contracts the lung adhesive: due to lack of surfactant hyaline
membrane disease, prematurity passive (relaxation}: a result of air
or fluid in the pleural space pleural effusion, pneumothorax
management: in the absence of a known etiology, persisting
atelectasis must be investigated (CT thorax) to rule out a
bronchogenic carcinoma
....._'
}-------------------,
,
DDx of Interstitial Disease Pulmonary edema Collagen disease
(e.g. fibrosis) Sarcoidosis Pneumoconiosis Metastatic disease (e.g.
lymphangitic permeation) Inflammatory conditions (e.g. early viral
pneumonia, interstitial pneumonia)
Toronto Notes 2011
Cheat lrnagins
Diapostic MedicallnlaginB DM7
CONSOLIDATION pathophysiology: fluid (water, blood),
inflammatory exudates, or tumour in alveoli signs air bronchograms:
lucent branching bronchi visible through opacification airspace
nodules: fluffy, patchy, poorly marginated appearance with later
tendency to coalesce, may take on lobar or segmental
distribution
cWferential fluid: pulmonary edema, blood (trauma, vasculitis,
bleeding disorder, pulmonary infarct) inflammatory exudates:
bacterial infections, TB, allergic hypersensitivity alveolitis,
bronchiolitis obliterans organizing pneumonia (BOOP), allergic
bronchopulmonary aspergillosis (ABPA), aspiration, sarcoidosis
tumour: bronchioalveolar carcinoma, lymphoma management: in the
absence of a known etiology, persisting atelectasis must be
investigated (Cf thorax) to rule out a bronchogenic
carcinomaINTERSTITIAL DISEASE pathophysiology: pathological process
involving the interlobular connective tissue (ie. "scaffolding of
the lung") signs
linear: fine lines caused by thickened connective tissue septae
Kerley A: long thin lines in upper lobes Kerley B: short horizontal
lines extending from lateral lung margin Kerley C: diffuse linear
pattern throughout lung nodular: 1-5 mm well-defined nodules
distributed evenly throughout lung seen in malignancy,
pneumoconiosis and with granulomas (sarcoidosis, miliary TB)
reticular (honeycomb): parenchyma replaced by thin-walled cysts
suggesting extensive destruction of pulmonary tissue and fibrosis
seen in interstitial pulmonary fibrosis (IPF), asbestosis and CVD
NOTE: watch for pneumothorax as a complication reticulonodular:
combination of reticular and nodular patterns may also see signs of
airspace disease (atelectasis and consolidation)
cWferential occupationallenvironmental exposure inorganic:
asbestosis, coal miner's pneumoconiosis, silicosis, berylliosis,
talc pneumoconiosis organic: bird fancier's lung, farmer's lung
(moldy hay) autoimmune: CVD, IBD, celiac diseae, vasculitis
drug-related: antibiotics (cephalosporins, nitrofurantoin), NSAIDs,
phenytoin, carbamazepine, fluoxetine, chemotherapy, heroin,
cocaine, methadone idiopathic: hypersensitivity pneumonitis, IPF,
BOOP management high resolution CT thorax biopsy
PULMONARY NODULE (see Table 5) signs: round opacity silhoutte
sign note: do not mistake nipple shadows for nodules; ifin doubt,
repeat CXR with nipple markers
cWferential atrapulmonary density: nipple, skin lesion,
electrode, pleural mass, bony lesion solitary nodule: tumour:
carcinoma, hamartoma, metastasis, bronchial adenoma inflammation:
histoplasmoma, tuberculoma, coccidioidomycosis vascular: AV
fistula, pulmonary varix (dilated pulmonary vein), infarct,
embolism multiple nodules: metastases, abscess, granulomatous lung
disease (TB, fungal, sarcoid, rheumatoid nodules, silicosis,
Wegener's disease) management clinical information and CT
appearance determine level of suspicion of malignancy ifhigh
probability, invasive testing (fine needle aspiration,
transbronchialltransthoracic biopsy) is indicated iflow
probability; repeat CXR or CT in 1-3 months and then every 6 months
for 2 years; if no change, then >99% chance benign
DDx for Cavibding Ling NoduleWEIRD HOLES Wegener's syndrome
Embolic (pulm0111ry, septic) Infection (111aerobes, pnewnocystis,
TB) RhliUfiiBtoid [necrobiotic: nodules) Developmental cysts
(sequeslration)Hisliocyloai5 Oncologiclll Lymphangioleiomyomalulil
Environmental, occupetiOIIII San:oidosis
DM8 Diapltic Mecllcal. ImagiDg
Chest Imging
1'oroDio
2011
Tabl111 S. Cllaracblristics af 14111ign ..d Mlllignallt
Pulmonary NadulasMlligl< ......
Mlfgil
11-llafinal!/spicaltlld ("corana 111diala"}
Wall-dalilad
I.QbuletedEccanlric or stippled
SmoathDilfusa. cantnt popcom. concanlric
2.0-4&0 days Cllllillltian. collapse, aclerqMdlrf, plaural
aflusi.m, lytic bona lailllt smliing hisloly
460 days
c-blia<llita Lllilnl
Ya&, apacialy wi1h Wlllllhkina&s > 15 nm.
ND
acctllbic ciMty llld shaggy illemal nwgiiS
No
Yes
Pulmonary Vascular AbnormalitiesPULMONARY EDEMA
&ifpu vucular redistribution/enlargement, pleural
c:ffusi.on, cardiomegaly (may be present in cardiogenic edema and
fluid overloaded states) edema. fluid iDitially collects in
interstitium: loss ofdefinition of pulmonary vasculature
peribronchial cuffing Kerley 8 lines reticulonodular pattern
thickening of interlobar fissures as pulmonary edema progresses,
fluid begins to collect in alveoli causing dUfuse air space disease
often ln a "bat wing" or "butterfly"' pattern in perlhilar regions
with tendency to spare the outermost lung fields differartial:
cardiogenic (CHF), renal failure. volume overload, non-cardiogenic
(ARDS)Figure 5. P11unl Ellusian i Lateral ViewPULMONARY EMBOLISM
lignl: Westermark sign (localized pulmonary oligemia), Hampton's
hump (triangular peripheral
in!arct), enlarged RV and RA, pulmonary edema, atelectasis,
pleural effusion JIUIDII8CIIle.DI: V /Q scan, CT angiography (look
for :filling defect)
Pleural AbnormalitiesPLEURAL EFFUSION
T1bla &. S1nlitivity af ...in Flm Viavn for Plaunl Effulion
25 ml- most sniliv& 50 ml- mrilcus seen in the pDS!sill'
cosloplumic sli:us2IXl mL
Dlfusa IIIZila&s
Figure 6. PnelllnOihonx
'.
.. ,
a horizontal fluid level is seen only in a hydropneumothorax
(both fluid and air within pleural cavity) effu&ion may aert
mass effect. shift trachea and mediastinum to opposite side, or
cause
Bllnted 1111111111....... Slftlltl: lntra-tlldDmil'lll pniCBII
Pragn11111:y Dillplwqma1ic plrlllysis Atllelrtuil lung
IIIIBclion
atelectasis ofadjacent lung U/S is superior to plain film for
detection of small effusions and may also aid in
thoracentesisPNEUMOTHORAX
PnaumonactDmy Pleu1111 ellu&ion alao may rest.fl in
eiiiVB!ioR. .,....._. .. Asl!ln.
COPD Large plau111l ellution T..nol6
&ifpu upright chest film allows visualization ofvisceral
pleura as curvilinear line paralleling chest wall. separating
partially collapsed lung from pleural air more obvious on
expiratory (increased contrast between lung and air) or lateral
decubitus film (air collects superiorly) more difficult to detect
on supine film; look for the deep (costopbrenk:) sulcus" sign.
double diaphragm sign (dome and anterior portions ofdiaphragm
outlined by lung and pleural respectively), hyperlucent hemithorax,
sharpening ofadjacent mediastinal structures mediastinal ahift may
occur ifair is under tension ("tension pneumothorax") differeDtial:
spontaneous (tall and thin males, smokers), iatrogenic (lung
biopsy, ventilation, CVP line insertion), trauma (associated with
rib fractures), emphysema, malignancy, honeycomb lung
Toronto Notes 2011
Cheat lrnagins
Diapostic MedicallnlaginB DM9
ASBESTOS
asbestos exposure may cause various pleural abnormalities
including benign plaques (most common) that may calcify, diffuse
pleural fibrosis, effusion, and malignant mesothelioma
Mediastinal AbnormalitiesMediastinal Mass the mediastinum is
divided into three compartments; this provides the approach to the
differential diagnosis of a mediastinal mass anterior (anterior
line formed by anterior trachea and posterior border ofheart and
great vessels) 4 T's: thyroid, thymic neoplasm (e.g. thymoma),
teratoma. and "terrible" lymphoma cardiophrenic angle mass
differential: thymic cyst, epicardial fat pad, foramen of Morgagni
hernia middle (extending behind anterior mediastinum to a line 1 em
posterior to the anterior border of the thoracic vertebral bodies)
esophageal carcinoma. esophageal duplication cyst metastatic
disease lymphadenopathy (all causes) hiatus hernia broncltogenic
cyst posterior (posterior to the middle line described above)
neurogenic tumour {e.g. neurofibroma. schwannoma) multiple myeloma
pheochromocytoma neurenteric cyst, thoracic duct cyst lateral
meningocele Bochdalek hernia extramedullary hematopoiesis in
addition, any compartment may give rise to lymphoma. lung cancer,
aortic aneurysm or other vascular abnormalities, abscess, and
hematomaENLARGED CARDIAC SILHOUETTEDDx Alml MMiilllltinalllaa 411
ThyroidThymus
T11111Dm1"Terrible- lymphoma
....am.
,
DDx !If lncre.ed Canliclthar1cic
Cardiomegaly (myocnial dilatationor hypertrophyI
P&ricardial effusion Poor inapil'lllllry llffortAow lung
volmes Pectus exCIVatum
heart borders on PA view, right heart border is formed by right
atrium; left heart border is formed by left atrium and left
ventricle on lateral view, anterior heart border is formed by right
ventricle; posterior border is formed by left atrium (superior to
left ventricle) and left ventricle cardiothoracic ratio = greatest
transverse dimension of the central shadow relative to the greatest
transverse dimension of the thoracic cavity in an adult, good
quality erect PA chest film, cardiothoracic ratio of >0.5 is
abnormal differential of ratio >0.5 cardiomegaly (myocardial
dilatation or hypertrophy) pericardia! effusion poor inspiratory
effort/low lung volumes pectus ex.cavatum ratio 7 em, splayed
carina (late sign) right ventricular enlargement elevation of
cardiac apex from diaphragm anterior enlargement leading to loss of
retrosternal air space on lateral increased contact of RV against
sternum left ventricular enlargement displacement of cardiac apex
inferiorly and posteriorly "boot-shaped" heart Rigler's sign: on
lateral film, from junction of IVC and heart at level of the left
hemidiaphragm. measure 1.8 em posteriorly then 1.8 em superiorly -+
if cardiac shadow extends beyond this point, then LV enlargement is
suggested note: not to be confused with Rigler's sign in the
abdomen
DMIO Diagnostic Medkal Imql.ng
Chest Imging
1'oroDio
2011
Tubes, Lines, and Catheters ensure appropriate placement and
assess potential complications oflines and tubes avoid mistaking a
line/tube fur pathology (e.g. oxygen rebreathcr IIUUk fur
pneumothoraces)Central Venous Catheter
prlma.rfiy used to administer tluids, medications, and vascular
acceas fur hemodialyais - also monitor central venous pressure
(CVP) tip must be located distal to (above) right atrium as this
prevents catheter from producing arrhythmias or perforating wall of
atrium ifmonitoring CVP - catheter tip must be proximal to venous
valves tip of well positioned central venous catheter projects over
silhouette ofSVC in a zone demarcated superiorly by the anterior
first rib end and clavicle and .i.Dferiorly by top of RA course
should paxallel course of SVC - ifappears to bend as it approaches
wall of SVC or appears perpendicular, catheter may damage and
ultimately perforate wall ofSVC compiJ.catioaJ: pneumothorax,
bleeding (mediastinal, pleural), air embolism frontal chest film:
tube projects over trachea and ahallow oblique or lateral chest
radiograph will help determine position in 3 dimensions progressive
gaseous disb:ntion of stomach on repeat imaging is concerning fur
esophageal intubation tip should be located 4 em above tracheal
carina- avoids selective intubation of right/left mainstem bronchus
as patient moves, low enough so it does not rub against vocal
chon:ls tube should not be inflated to the point that it
continuously and completely occludes tracheal lumen as it may cause
pressure induced necrosis of trachealJllUCOsa and predispose to
rupture or stenosis .maximum inftation diameter 6 mm in outer
diameter), enhancement of appendiceal wall, adjacent inflammatory
stranding, appendicolith; a1so facilitates percutaneous abscess
drainage Acute Diverticulitis most common site is rectosigmoid
(diverticula are outpouchings of colon wall) CT is imaging modality
of choice, although U/S is sometimes used oral and rectal contrast
given before CT to opacify bowel cardinal signs: thickened wall,
mesenteric infiltration, gas-filled diverticula, abscess CT can be
used for percutaneous abscess drainage before or in lieu of
surgical intervention sometimes difficult to distinguish from
perforated cancer (therefore send abscess fluid for cytology and
follow up with colonoscopy) if chronic, may see fistula (most
common to bladder) or sinus tract (linear or branching structures)
Acute Pancreatitis clinical/biochemical diagnosis imaging used to
support diagnosis and evaluate for complications (diagnosis cannot
be excluded by imaging alone) U/S good for screening and follow-up
of a hypoechoic enlarged pancreas (although useless if ileus
present as gas obscures pancreas) CT is useful in advanced stages
of pancreatitis and in assessing for complications and is
increasingly becoming the 1st line imaging test enlarged pancreas,
edema, stranding changes in surrounding fat with indistinct fat
planes, mesenteric and Gerota's fascia thickening, pseudocyst in
lesser sac, abscess (gas or thickwalled fluid collection),
pancreatic necrosis (low attenuation gas-containing non-enhancing
pancreatic tissue), hemorrhage CT-guided needle aspiration and/or
drainage done for abscess when clinically indicated pseudocyst may
be followed by CT and drained if symptomatic
Angiography of Gl Tract GI tract arterial blood supply celiac
artery: hepatic, splenic, gastroduodenal, left/right gastric
superior mesenteric artery (SMA): jejunal, ileal, ileo-colic, right
colic, middle colic inferior mesenteric artery (IMA): left colic,
superior rectal imaging of GI tract vessels conventional angiogram:
invasive (usual approach via femoral puncture), catheter used flush
aortography: catheter injection into abdominal aorta, followed by
selective arteriography of individual vessels CT angiogram:
non-invasive using IV contrast (no catheterization required)
Genitourinary SystemModalitiesKUB (kidneys, ureters, bladder} a
frontal supine radiograph ofthe abdomen useful in evaluation of
radio-opaque renal stones (all stones but uric acid and indinavir),
as well as indwelling ureteric stents or catheters addition of
intravenous contrast excreted by the kidney (intravenous urogram)
allows greater visualization of the urinary tract, but has been
largely replaced by CT urography
....
,,
..,_ntltion Acuhl tntic!W pain = Doppler, UIS Amllnonhaa = UIS.
MRI (brailf
Imaging Moll..ity Bun on
Flank pail = U/S, CT Hermduril = UIS, Cystoscopy, CT Infertility
= Hystaroulpingooram. MRI Lowsr abdominal mass= UIS. CT Lower
abdominal pain = U/S, CT R811111 colic = UIS. KUB, CT Tasticular
m111 = UIS Unrthnll stricture
Bl011ting = UIS. CT
= Ure!hflJIIfllm
DMlt!i Diagnostic Medkal Imql.ng
1'oroDio
2011
Abdomi1111l CT plainCT good for general imaging of renal
anatomy, although specific study types have supplanted plain CT for
many indications, including CT urography (upper tract uroepithclial
(renal masses) malignancies and renal calculi) and triphasic
cr 111'0JP'8phy
cr
ac.retory phase Imaging all.owa detafted assessment of urinary
tract& high sensitivity (95%) for uroepi.thelial malignancies
of the upper urinary tracts also useful fur usessment of renal
calculi triphaeic CT standard imaging fur renal masses comprised of
unenhanced, nephrographlc, and excretory phaaea allows accurate
asseasment of renal arteries and veins and better characterization
of suspldous renal masses, with particular utility in
differentiating renal cell carcinoma from more benign masses
U/S initial study for evalUiltion of kidney size and nature of
renal masse& (solid VII. cystic renal masses VII. complicatl:d
cysts) technique of choice for screening patients with suspected
hydronephrosis (no intravenous contrast InJection. no radiation to
patient, and can be used in patients in renal failure) solid renal
masses: echogenic (bright on U/S) cystic renal masses: smooth
well-defined walls with anechoic interior (dark on U/S) complicated
cysts: internal echoes within a thlclcened, irregular-walled cyst
transrectal U/S (TRUS) useful to evaluate prostate gland and guide
biopsies Doppler U/S to assess renal VB.llculatuze
Figure I. Triphlllic CT af an showing fat density with
non-contrast scan. mildly anhandng with clllllrast
Retrograde Pyelography used to visualize the urinary collect:ing
system via a cystoscope, ureteral catheterlzatlon, and retrograde
InJection of contrast medium ordered when the intrarenal collecting
system and ureters cannot be opacl1ied using Intravenous techniques
(patient with impaired renal function, high grade obstructi.on)
only yields information about the collecting systems (renal pelvis
and usociated structures) no information regarding the parenchyma
ofthe kidney Voiding Cystourethrogram (VCUG) bladder filled with
contrast to the point where voldlng is trlggered real-time Images
via fluoroscopy (continuous x-ray imaging) to visualize bladder
contractility and evidence ofvesicoureteric reflux Indicat!ons:
children with recurrent UTis, hydronephrosis, hydroureter,
suspected lower urinary tract obstruction or vesicoureteral
reflux
Retrograde Urethrogram used mainly to study strictures or trauma
to the male urethra (Figure 10)
MRI strengths: high spatial and tissue resolution, lack of
exposure to ionizing radiation and nephrotoxic contrast agents
indicated over CT for depiction of renal masses in patients with
previous nephron sparing surgery, patients requiring serial
follow-ups (less radiation dosage), patients with reduced renal
function. and patients with 90litary kidneysRenal Scan 2
radionucllde testa for kidney - renogram and morpbologl.cal scan
renogram to assess renal function and collecting system useful in
evaluation ofrenal failure, workup of urinary tract obstruction and
hypertension, investigation of renal transplant intravenous
injection of a radionuclide, technetium-99m. pentetate
(Tc99m.-DTPA) or iodine-labeled hippurate, and imaged at 1-second
intervals with a gamma camera over 30 minutes to assess perfusion
delayed static images over the nat 30 minutes can be used to assess
renal function andthe collecting system
Figure 9. Tltph811c CT af a R111a1 Cell CarciDml- showing
arterial anhancamant and vanaua da-anhancamant
Uratllro.-m - demons'b'lting stricbJre in tha mambranaua
urethra
Figure 1D. RlltrtJarada
morphologl.cal to assess renal anatomy study done with
Tc99m-DMSA and Tc99m-glucoheptonate useful in investigation of
renal mass and cortical scars
'IbroDlo Nota 2011
DiagnollkMedical Jma&lDg DM17
Gynecological Imaging transabdominal and transvaginal are the
primary modalities, and are indicated for different scenarios
transabdominal requires a full bladder to push out air containing
loopa of bowel
U/S
good initiallnvestlgatlon for suspected pelvic pathology
transvaginal approach provides enhanced detail of deeper/smaller
structures by allowing use of higher frequency sound waves 81:
reduced distances improved aase811ment of ovarie111, first
trimester development. and ectopic pregnanciesHysterosalplngogram
useful for assessing pathology of the uterine cavity and fallopian
tubes, performed by x-ray images of the pelvis after cannulation of
the cervix and subsequent injection ofopacifying agent particularly
useful for evaluating uterine abnormalities (bicornuate uterus), or
evaluation of fertility (absence offlow from tubes to peritoneal
cavity indicates obstruction)
Flg1ra 11. TranuiMiomlul Ultrasaund- pregnancy, 18 vvk fetus
CT/MRI
excellent for evaluating pelvic structure111, especially those
adjacent to the adnexa and uterus invaluable for staging
gynecological malignancies
Selected Pathology
F"1111ra 12. Hptaroaalpingapamshowing left hydrosalpinxI
Renal Masses Bozniak classification for cystic renal masses
classes I-II are benign and can be disregarded class IIF should be
followed duseslll-IV are suspicioW!I for malignancy, requiring
additional workupTable 1z. Boznlak Claultlcllloa for Cystic Renal
Ma1881Sill,.. 1'111111 cylll Clnll Clnlll
-----------------------------------------
out by bllla-HCG before CT of afvmale pelvi (or any orgm
performlid.
lhould always ba rulad i
Sane as class I + tile caaticatian ar lllllllerai:By11ickened
c*ilicatian in septae II' Wills; also includes cys11 1 em} lhlt do
not mnce with contrat CSF > air I= dark)
Co..lartRicym Clnllll
1lick
wals. caleific:atians. sep11118d. emn:ing Wills II' sapta with
contrast
Atllludol
Rial call . . . . . a.. IV
Sirna as class II +salt tissue enhalv:anent with cantrast
(dllinad as >10 Hounsfield Wlit R:rease. L"hanll:larizing
wacuBityj with dHnharn:mant in VIllOUS phasa nas af niCIDSis
..... ,
angiomyollpoma (a benign renal neoplasm comp