Peritoneum General features• The peritoneum is a thin serous

membrane that lines the walls of the abdominal and pelvic cavities and cover the organs within these cavities.

. Also called Serosa.

. Consists of a layer of flattened mesothelial cells lying on a layer of loose connective tissue.

LAYERS.

1.Parietal layer lines the wall of abd. And pelvic cavities.

2.visceral layer covers the organs.

Peritoneal cavity .is a potential space between the two layers of peritoneum. . filled with very thin film of serous fluid secreted by the mesothelial cells.

.In the male, is a closed sac, but in the female,it is open bcz of uterine tubes, the uterus, and the vagina.

Extraperitoneal connective tissue. Present b/w parietal layer and abd. and pelvic walls.

• Peritoneal fluid• Peritoneal fluid is pale yellow

fluid rich in leukocytes• Mobile viscera glide easily on one

another.• Peritoneal fluid moves upward

towards subphrenic spaces- whatever the position of the body- by:

• 1- Movements of diaphragm.• 2- Movements of abdominal

muscles• 3- Peristaltic movements

Functions of peritoneal fluid

• lubrication.• Absorbption• Support viscera• MOVEMENT

Divisions of peritoneal cavity

It is divided into two main sacs:

1- Greater sac.

2- Lesser sac or omental bursa.

These two sacs are interconnected by a single oval opening called the epiploic foramen or opening into lesser sac or foramen of Winslow

The relationship between viscera and peritoneum

• Intraperitoneal viscera －• viscera completely surrounded by peritoneum

• stomach, superior part of duodenum, jejunum, ileum, cecum, vermiform appendix, transverse and sigmoid colons, spleen and ovary

• Retroperitoneal viscera • － some organs lie on the posterior abdominal wall and are covered by peritoneum

on their anterior surfaces only.

Primary retroperitoneal organs

kidney suprarenal gland Aorta and ivc Ureter Rectum(lower third part)

Sec.retroperitoneal organs

• Pancreas(head,neck,body) while tail lies in splenrenal ligament.

• Duodenum 2nd and third part.

• Ascending and descending colon.

Structures which are formed by peritoneum

.Peritoneal folds.

.Peritoneal ligaments. . Falciform. . rt and lt triangular.

.coronary..Omentum stomach. MESENTRY Small intestine.

.Mesocolon Transverse mesocolon Sigmoid mesocolon Meso appendix.

Peritoneum of liver

• The liver is almost completely covered in visceral peritoneum, and only the ‘bare area' is in direct contact with the right dome of the diaphragm. Peritoneal folds, the ligaments of the liver, run from the liver to the surrounding viscera and to the abdominal wall

Peritoneum of liver.

• Falciform ligament of liver Consists of double peritoneal

layer – Sickle shape– Extends from anterior

abdominal wall to liver just rt to midline.

– Free border of the ligament contains Ligamentum teres (obliterated umbilical vein)

Its two peritoneal layers divide to enclose the liver and are continuous with the visceral peritoneum that is adherent to the surface of the liver. Superiorly, they are reflected onto the inferior surface of the diaphragm and are continuous with the parietal peritoneum over the right dome. At the posterior limit, or apex, of the falciform ligament, the two layers are also reflected vertically left and right, and are continuous with the anterior layers of the left triangular ligament and the superior layer of the coronary ligament of the liver.

Coronary ligament

• Peritoneum that lines the under surface of diaphragm is reflected on to superior surface of rt lobe of liver forming the upper layer of coronary ligament

• Then, it descends from sup surface of liver to ant surface then inferior surface of liver.

• From post part of inferior surface peritoneum reflected on to front of right kidney & rt suprarenal gland forming the lower layer of coronary ligament.

• The lower & upper layers of coronary ligament bound a large area on the post surface of the liver called bare area of the liver which has no peritoneal covering.

Rt triangular ligament. .Short v shaped fold..Formed by approximation of two

layers of coronary ligament on rt lateral end.

Left triangular ligament..Double layer..On upper border of lt lobe..Upper layer continues with left

layer of falciform ligament..Lower layer with lt layer of lesser

omentum.

• Hepatogastric ligament•

• Hepatoduodenal ligament

Peritoneum of stomach

.greater omentum.lesser omentum

.hepatogastric ligamentum .gastrosplenic ligament

.gastrocolic

Greater omentum - largest peritoneal fold which hangs inferiorly from the greater

curvature of stomach. -double sheet,each sheet has two layers of peritoneumseparated by

scanty connective tissue. Anterior sheetAnterior layer From ant surface of stomach and duodenum.Posterior layer From post surface of stomach and pylorus. Two layers of anterior sheet decend from greater curvature to

a variable distance in peritoneal cavity Ascend back on itself to form posterior sheet. Posterior sheet Anterior layer forms posterior wall of lesser sac. Post layer passes infront of transvers colon n mesocolon n

attatched to t.mesocolon at its root to form gastrocolic ligament.

• Lesser Omentum

• Connects liver to stomach.

• attached above to porta hepatis & fissure for ligamentum venosum inferiorly to lesser curvature of the stomach,& 1st inch of duodenum.

• Attatchment is L shaped.

• Forms ant wall of lesser sac

• Its free margin contains:Portal vein: PosteriorBile duct : Anterior &

rightHapatic artery: anterior and left.

Hepatogastric ligament Gastrosplenic ligament

Gastrophrenic ligament Gastrocolic ligament

Omental bursa or lesse sacIt is a subsection of peritoneal cavity behind the stomach.Position－ situated behind the lesser omentum and stomachWalls• Superior• － peritoneum which covers the caudate lobe of liver and diaphragm• Anterior• － formed by lesser omentum, peritoneum of posterior wall of

stomach, and anterior two layers of greater omentum• Inferior• － conjunctive area of anterior and posterior two layers of greater

omentum.bcz of fusion cant extend much below transverse colon.• Posterior• － formed by posterior two layers of greater omentum, transverse

colon and transverse mesocolon, peritoneum covering pancreas, left kidney and suprarenal gland

. Left－ formed by the spleen,

gastrosplenic and splenorenal ligament

• Right－ formed by omental

foramen

The Omental bursa (lesser sac) communicates with the greater sac through the omental foramen.

Epiploic Foramen Boundaries2.5cm vertical slit.Anterior: free margin of lesser omentum, containing (hepatic artery, bile duct and portal vein)Posterior: peritoneum covering IVC.Superior: Caudate process of the caudate lobe of the liver.Inferior: 1st inch of the1st part of duodenum.

spleen

The spleen lies in the left hypochondrium between the stomach and diaphragm.It has two ends, three borders and two surfaces.

pe : 3 borders, 2 ends, 2 surfaces.

A. Ends1) lateral end (Broad)2) medial end (tapering)

B. BordersUpper(Anterior) border:

Sharp & notched

Lower (Posterior)border: (Broad)

Intermediate border: thick, incomplete. Extends from the medial end till the hilum).

Ligaments of spleen

• Gastrosplenic ligament － a double layer of peritoneum that connects the

fundus and greater curvature of stomach to hilum of spleen. Has two layers.ant and post.

• Splenorenal ligament • － extends between the hilum of spleen and anterior

aspect of left kidney. The splenic vessels lies within this ligament, as well as the tail of pancreas

• Phrenicosplenic ligament• Splenocolic ligament • Phrenicocolic ligament.

If the peritoneal attachments of the spleen are not recognized during surgery, the splenic capsule is at risk of injury and there may be subsequent serious bleeding. Downward traction on the phrenicocolic ligament during handling of the descending colon, especially during mobilization of the splenic flexure, may cause rupture of the splenic capsule. This is less likely if traction on the phrenicocolic ligament is made laterally or medially. The superior border and anterior diaphragmatic surface of the splenic capsule are often adherent to the peritoneum of the greater omentum. Medial traction on the omentum during surgery may cause splenic capsular injury: such injury is less likely, if any limited traction required is applied inferiorly

Transverse mesocolon

Transverse mesocolon － a double fold of peritoneum reflected from post abd wall and suspends the transverse colon in the peritoneal cavity.

• Root of t.mesocolon.• Lies along an oblique line passing from ant aspect of 2nd part of

duodenum,over the head and neck of pancreas,above the duodenojejunal junctionn over the upper pole of left kidney to the splenic flexure.

• Contains middle colic vessels together with the branches of sup mesenteric plexus,lymphatics and regional lymph nodes.

• Two layers from post abd wall reach on post surface of colon,cover it then upper layer becomes continues with the post.layer of g.omentum to which it is adherent.

• Lower layer continues with peritoeum of post.abd wall.

Extension of t.mesocolon.

• Duodenocolic ligamentFrom hepatic flexure to 2nd part of duodenum.

• Phrenicocolic ligament.From splenic flexure to diaphragm at level of

11th rib.

Mesentery of small intestine• Fan shaped with two layers anterosup and

posteroinf separated by c.t. and vessels.• Root of mesentry.• A diagonal line from duodenojej flexure on the left

of 2nd lumber vert body to the rt sacroiliac joint.• Length is 15cm in adults.n 6 meter when cover

intestineal loops.• Its two layers contain sup.mesenteric vessels.

Mesoappendix • Triangular mesentery －

extends from terminal part of ileum to appendix

• Appendicular artery runs in free margin of the mesoappendix

Divisions of peritoneal cavity

• The greater sac can be divided into two compartments.

• Supracolic or supramesocolic• Infracolic or inframesocolic

Supramesocolic The supramesocolic space lies above the transverse mesocolon between the diaphragm and the transverse colon.divided into right and left supramesocolic spaces.

The right supramesocolic space can be divided into three subspaces; the right subphrenic space, the right subhepatic space, the lesser sac..

Right subphrenic space lies between the diaphragm and the anterior, superior and right lateral surfaces of the right lobe of the liver

Boudaries left --------- ( falciform ligament ) behind ---------(upper layer of the coronary ligament.)

clinical impcommon site for collections of fluid after right sided abdominal inflammation.

The right subhepatic space lies between the right lobe of the liver and the right kidney.Boundaries

--superiorly ( inferior layer of the coronary ligament)-- laterally ( right lateral abdominal wall,) --posteriorly ( anterior surface of the upper pole of the right kidney) --medially ( second part of the duodenum, hepatic flexure, transverse mesocolon and part of the head of the pancreas.Clinical imp. In the supine position the posterior right subhepatic space is more dependent than the right paracolic gutter: postoperative infected fluid collections are common in this location

The left supramesocolic space

• can be divided into two subspaces; the left subphrenic space and the left perihepatic space

Left subphrenic space lies between the diaphragm, the anterior and superior surfaces of the left lobe of the liver, the anterosuperior surface of the stomach and the diaphragmatic surface of the spleen.

boundaries right by the falciform ligament behind by the anterior layer of the left triangular ligament. Clinical imp ---- It is much enlarged in the absence of the spleen and is a common site for fluid collection particularly after splenectomy. -----larger than the right and divided into anterior and posterior parts, although no obvious demarcation exists in the absence of disease. -----The left posterior subphrenic space is small and lies between the fundus of the stomach and the diaphragm above the origin of the splenorenal ligament. ------The left anterior subphrenic space is large and lies between the superior and anterolateral surfaces of the spleen and the left dome of the diaphragm. Inferiorly and medially, this space is bounded by the splenorenal, gastrosplenic, and phrenicocolic ligaments which produces a partial barrier to the left paracolic gutter.------- This may explain why left subphrenic collections are less frequent than right subphrenic collections following lower abdominal and pelvic surgery, but the left subphrenic space is the commonest site of fluid collection after upper abdominal, particularly splenic, surgery.

Left perihepatic space • The left perihepatic space is sometimes subdivided into

anterior and posterior spaces.• The posterior perihepatic space is also known as the left

subhepatic space or gastrohepatic recess. • The left anterior perihepatic space lies between the

anterosuperior surface of the left lobe of the liver and diaphragm. The left posterior perihepatic space lies inferior to the left lobe of the liver, and extends into the fissure for the ligamentum venosum on the right, anterior to the main portal vein. Posteriorly, the lesser omentum separates this space from the superior recess of the lesser sac. On the left, the space is bounded by the lesser curvature of the stomach.

INFRAMESOCOLIC COMPARTMENT

. lies below the transverse mesocolon and transverse colon are far as the true pelvis.

.divided in two unequal spaces by the root of the mesentery of the small intestine.

. contains the right and left paracolic gutters lateral to the ascending and descending colon. As a consequence of the mobility of the transverse mesocolon and mesentery of the small intestine, disease processes are rarely well contained within these spaces, and fluid within the infracolic space tends to descend into the pelvis or the paracolic gutters

Right infracolic space The right infracolic space is a triangular space. It is smaller than its counterpart on the left, and lies posterior and inferior to the transverse colon and mesocolon and to the right of the small intestinal mesentery. The vermiform appendix often lies in the lower part of the right infracolic space.Left infracolic space The left infracolic space is larger than its counterpart on the right and is in free communication with the pelvis to the right of the midline. It lies posterior and inferior to the transverse colon and mesocolon and to the left of the mesentery of the small intestine. The sigmoid colon and its mesentery may partially restrict the flow of fluid or blood into the pelvis to the left of the midline

Paracolic gutters

..right and left paracolic gutters are peritoneal recesses on the posterior abdominal wall lying alongside the ascending and descending colon.The right (lateral) paracolic gutter runs from the superolateral aspect of the hepatic flexure of the colon, down the lateral aspect of the ascending colon, and around the caecum. It is continuous with the peritoneum as it descends into the pelvis over the pelvic brim. Superiorly, it is continuous with the peritoneum which lines the hepatorenal pouch and, through the epiploic foramen, the lesser sac.

Clinical importance• Bile, pus or blood released from viscera anywhere along its

length may run along the gutter and collect in sites quite remote from the organ of origin. In supine patients, infected fluid from the right iliac fossa may ascend in the gutter to enter the lesser sac. In patients nursed in a sitting position, fluid from the stomach, duodenum or gallbladder may run down the gutter to collect in the right iliac fossa or pelvis and may mimic acute appendicitis or form a pelvic abscess. The right paracolic gutter is larger than the left, which together with the partial barrier provided by the phrenicocolic ligament, may explain why right subphrenic collections are more common than left subphrenic collections

Because the peritoneum of the falciform ligament is continuous with that covering the posterior abdominal wall and the periumbilical anterior abdominal wall, blood arising from retroperitoneal haemorrhage (commonly acute haemorrhagic pancreatitis) may track between the folds of peritoneum and appear as haemorrhagic

discolouration around the umbilicus (Cullen's sign). Inflammatory change from the pancreas may spread via the gastrohepatic ligament (lesser omentum) and then via the falciform ligament to the umbilicus

The recess formed between the peritoneum of the inferior surface of the liver, the hepatorenal ligament and the peritoneum over the right kidney is known as the

hepatorenal pouch (of Morison). In the supine position this is the most dependent part of the peritoneal cavity in the upper abdomen, and is a common site of pathological fluid accumulation.

Folds and fossas of anterior abdominal wall

• Medial umbilical fold －contain the remnant of urachus (median umbilical ligaments)

• Medial umbilical fold －contains remnants of the umbilical arteries (medial umbilical ligaments)

• Lateral umbilical fold －contains the inferior epigastric vessels

• Supravesical fossa• Medial inguinal fossa • Lateral inguinal fossa

Folds and fossas of anterior abdominal wall

• Medial umbilical fold －contain the remnant of urachus (median umbilical ligaments)

• Medial umbilical fold －contains remnants of the umbilical arteries (medial umbilical ligaments)

• Lateral umbilical fold －contains the inferior epigastric vessels

• Supravesical fossa• Medial inguinal fossa • Lateral inguinal fossa