Fascia of the Abdomen

FASCIA OF THE ABDOMEN

Chris van ZylKHC

Outline Peritoneum

Embryology Anatomy

Quick word on Fascia of the anterior abdominal wall Fascia around kidneys

Peritoneam

Serous membrane Divided into parietal

and visceral Parietal peritoneum

lines anterior, lateral and posterior walls peritoneal cavity

Visceral peritoneum lines all the organs that are intraperitoneal.

Embryology Mesentries divide coelomic cavity into R

+ L halves Upper abdomen

Stomach + gut suspended in the middle Liver in the ventral mesentery Spleen in dorsal mesentery

Embryology Organs migrate in anticlockwise fashion

Liver lies on the right Spleen on the left

Drags mesenteries into position they occupy in muturity

Peritoneal cavity

Two main regions Greater sac (general abdominal cavity) Lesser sac (or omental bursa)

Communicate via foramen of Vinslow (epiploic foramen)

Course Covers the

inferior aspect of diaphragm and is reflected onto the liver and the abdominal part of the esophagus

After the liver is enclosed, it extends from the porta hepatis as a double layer (lesser omentum) to the lesser curvature of the stomach

It encloses the stomach, reaches the greater curvature of stomach and extends as a double layer (greater omentum) down into the abdominal cavity,loops back up to the transverse colon.

From there the transverse mesocolon is formed, which joins the post abdominal wall on the anterior aspect of the pancreas

Course

Double layer devides into single layers one which runs superiorly over

the post abdominal wall and reflected onto the bare area of liver

The other runs inferiorly over the post abdominal wall to cover the pelvic organs and join the peritoneum of the anterior abdominal wall.

The post peritoneal layer of the post abdo wall is interrupted as it’s reflected from the duodenojejenal to ileocaecal junction to form the mesentery of the jejenum and ileum

Course

Blood supply of the peritoneumTo the parietal peritoneum Lumbar vessels Branches of the inferior and superior

epigastric arteries Musculophrenic arteries Deep circumflex arteries

To the visceral peritoneum From the arteries supplying the

appropriate viscera

Innervation of the peritoneum

To the parietal peritoneum From the nerves supplying the

diaphragm and adjacent body wall - e.g. phrenic (C3-C5) and intercostal and subcostal nerves (T7-L1)

To the visceral peritoneum Sympathetic nerves innervating the

appropriate viscera.

Anatomy devided into:

Peritoneal spaces Peritoneal reflections including ligaments Mesentry Omenta

Peritoneam

Peritoneal Spaces: Peritoneal cavity

devided by transverse colon and mesocolon into: Supramesocolic

compartment Right and Left

supramesocolic spaces Inframesocolic

compartment Devided by root of

smallbowel mesentery Right and Left

inframesocolic spaces

Right supramesocolic spaceDevided into: Right subphrenic space

Diaphragmatic surface of R liver from falciform ligament medially to coronary ligament postero-infer

Right subhepatic space Subdevided into ant + post

spaces (Morrison’s pouch) Communicates with R

paracolic gutter + R infracolic space

Lesser sac

Left supramesocolic spaceDevided into: Ant left perihepatic

space Post left perihepatic

space (gastrohepatic recess)

Anterior left subphrenic spaces

Posterior left suphrenic spaces

RSP: R subphric S

LSP: L subphrenic S

LPC: L paracolic S

LSs: Sup recess LS

Lsi: Inf recess LS

Imaging

Lesser Sac Posterior Wall

Peritoneum over pancreas, left adrenal, upper pole of left kidney

Anterior Wall Peritoneum over post.

stomach, lesser omentum Lateral Wall

Spleen, gastrosplenic, splenorenal ligaments

Communicates via epiploic foramen (of Winslow)

Lesser sac

Devided by gastropancreatic fold (left gastric artery) Superior recess

Encloses caudate lobe

Inferior recess Lies between

stomach and pancreas

Left Gastric artery: Arrow

GHL: Gastro hepatic lig

SHS: Subhepatic SLSs: Sup recess LSLsi: Inf recess LS

Foramen of Winslow Post: IVC Ant: free edge of lesser omentum

containing portal vein, hepatic artery, CBD Sup: Caudate lobe Inf: 1st part of duodenum

Right inframesocolic compartment

Bounded by: Transverse

mesocolon sup and to the R

Root of small bowel mesentery

Left inframesocolic space Larger than right In free communication with pelvis right

to midline Sigmoid colon and mesentery forms

partial barier left of midline

Paracolic gutters Peritoneal recesses lat to ascending +

descending colon Right continuous with right

subhepatic/phrenic spaces Left seperated by phrenicocolic ligament Both communicates with pelvis

Imaging: Inframesocolic compart.

Pelvic peritoneal spaces/pouches The rectouterine pouch/ Pouch of

Douglas (in females) separating rectum from bladder

The rectovesical pouch (in males) separating the rectum from the bladder

The vesicouterine pouch (in females) separating bladder from uterus

Peritoneal reflections 8 Legaments 4 Mesentries 2 Omenta

Peritoneal ligaments Right coronary

ligament Reflection of

peritoneum from diaphragm to post surface of R liver lobe

Bare area between two layers of this ligament

Left coronary ligament Continuation of this

peritoneal reflection to the left

Peritoneal ligaments Gastrosplenic ligament

Continuous with greater omentum From greater curve of stomach to spleen. Contains gastroepiploic vessels + short gastric

vessels

Falciform ligament From anterosup surface of liver to diaphragm +

ant abdominal wall Carries lig Teres (obliterated umbilical vein) in

free edge Continues with fissure for lig venosum

Peritoneal ligaments Phrenicocolic ligament

From splenic flexure to diaphragm Continuous with transverse mesocolon +

splenorenal lig Splenorenal ligament

From pancreatic tail to splenic hilus Transmits splenic vessels

Peritoneal ligaments Hepatoduodenal ligaments

From flexure between 1st + 2nd part of duodenum to porta hepatis

Transports portal triad Duodenocolic ligament

From R colic flexure to descending duodenum

Continuous with transverse mesocolon

Imaging

Imaging

Broad ligament of the uterus Wide fold of peritoneum that connects the sides

of the uterus to the walls and floor of the pelvis

Subcomponents: Mesometrium- the mesentery of the

uterus; the largest portion of the broad ligament

Mesosalpinx- the part that surrounds the Fallopian tube

Mesovarium- the part that connects the anterior surface of the ovary to the remainder of the broad ligament.

Broad ligament of the uterus

Mesentries Small bowel mesentry

Broad fan shaped fold Conects jejunum + ileum to post abdominal

wall Extends from duodenojejunal flexure (Left

of L2) to upper part of R SI joint Root continuous with L + R ant pararenal

spaces Contains jejunal, ileal branches of SMA and

accompanying veins, nerves, lymphatics

Mesentries Transverse mesocolon

Connects transvers colon to post abdominal wall

Pass from ant head and body of pancreas to post colon

Upper layer adherent to greater omentum Contains middle colic vessels, nerves +

lymphatics

Mesentries Sigmoid mesocolon

Attaches sigmoid colon to pelvic wall

Line of attachment inverted V with apex near devision of L common iliac artery

Leftlimb descends to L psoas, R into pelvis

Contains sup rectal vessels

Mesoappendix Attached to lower end of

small bowel mesentry

Omenta Greater and Lesser

Greater Omentum

Hangs from the greater curve of the stomach and loops down in front of the intestines before curving back upwards to attach to the transverse colon, thus 4 layers of peritoneum 

Continuous with: Gastrocolic ligament: largest component Gastrosplenic ligament: to splenic hilus Gastrophrenic ligament

Lesser Omentum Attached to the lesser curvature of the

stomach, prox duodenum and the liverSubdivided into:  Gastrohepatic ligament

connects the left lobe of the liver to the lesser curvature of the stomach

Hepatoduodenal ligament free edge of the omentum, extends to porta

hepatis and ligamentum venosum Contains gastric artery, coronary vein,

left gastric nodal chain

Superficial fascia Superficial layer Deep layer

Transversalis fascia

Fascia of anterior abdominal wall

2: Superficial layer

3: Deep layer

8: Transversalis fascia

Superficial fascia Single layer superiorly containing

variable ammounts of fat Inferiorly devides into superficial and

deep layers Superficial layer (Fascia of Camper):

Passes over inguinal ligament Continuous with superficial fascia of the thigh Continues in the scrotum as the fascia of

Dartos

Superficial fascia

Deepy layer (Fascia of Scarpa): Connected to aponeurosis of external oblique

laterally + linea alba/ symphisis pubis medially Passes over inguinal ligamnet inferolaterally to

fuse with fascia of the thigh Forms superfiscial perineal fascia

inferomedially (Fascia of Colles)

Transversalis fascia Lies between transverse abdominis and

extraperitoneal fat Continuous with inferior diaphragmatic

fascia Fuses with thoracolumbar fascia

posteriorly Spermatic cord/Round ligament passes

through transversalis fascia at deep inguinal ring becomes internal spermatic fascia

Fascia around kidneys Renal fascia situated around the

perirenal fat Devided into:

Anterior fascia (Gerota’s) Continuous with R inf coronary ligament

Posterior fascia (Zuckerkandl’s) Continous with diaphragmatic fascia and iliacus

fascia Fused laterally as conal fascia

Continuous with transversalis fascia Fused medially with sheeths of aorta + IVC

Fascia around kidneys

References: Applied Radiological Anatomy

Paul Butler, Adam W. M. Mitchell, Harold Ellis Anatomy for Diagnostic Imaging

Stephanie Ryan, Michelle McNicholas, Stephen Eustace Third Edition