Peritoneal folds- lesser omentum & greater omentum

PERITONEAL FOLDS

• Peritoneal folds serve as pathways for neurovascular structures to reach the organs from abdominal wall.
• Name of the peritoneal fold may be as follows:

1. Peritoneal folds attach to stomach are called Omenta: Lesser omentum & Greater omentum.
2. Peritoneal fold suspending intestine is called mesentry.
3. Folds of peritoneum connecting organs to rach other or to abdominal wall are called Ligaments.

 OMENTA

1.  GREATER OMENTUM

• It is large 4 layered peritoneal fold hanging down like an apron from greater curvature.
• Anterior two layers descend from greater curvature of stomach to a variable extent, & fold upon themselves to form posterior two layers, i.efirst layer becomes the fourth layer & second layer becomes third layer.
• The part of the peritoneal cavity called lesser sac b/w 2nd & 3rd layer gets obliterated, except for aboit 2.5cm below the greater curvature of stomach.
• Greater omentum contains the right & left gastroepiploic vessels which anastomose with each other in the interval b/w the first two layers.
• Greater omentum acts as storehouse of fat.
• Greater omentum is generally referred to as “policeman of abdomen” because it adheres to areas of inflammation, wrapping around inflammed organs, localising the infections & preventing serious diffuse peritonitis.
• It develops from caudal part of dorsal mesogastrium.

2. LESSER OMENTUM

• It extends from liver to stomach (lesser curvature) & duodenum (first 2cm).
• The part of lesser omentum from liver to stomach is called hepatogastric ligament, & part from liver to duodenum is called hepatoduodenal ligament.
• Hepatogastric ligament forms anterior free wall of lesser sac (omental bursa) & contains right & left gastric vessels, branches of gastric nerves & lymph vessels.
• Hepatoduodenal ligament forms right free margin, containing portal vein, hepatic artery proper, bile duct, lymphatics & hepatic plexus of nerves.
• Lesser omentum develops from ventral mesogastrium (dorsal part).