lesser omentum
Summary
The lesser omentum is a double-layered peritoneal fold connecting the lesser curvature of the stomach and the proximal duodenum to the liver. It consists of the hepatogastric ligament and hepatoduodenal ligament, the latter containing the portal triad (portal vein, hepatic artery proper, common bile duct).
Detail
The lesser omentum is derived embryologically from the ventral mesentery of the foregut. It has two main parts: the hepatogastric ligament (connects lesser curvature of stomach to liver) and the hepatoduodenal ligament (connects the first part of the duodenum to the liver). The hepatoduodenal ligament is clinically significant because it encloses the portal triad—the portal vein, hepatic artery proper, and common bile duct—which can be compressed manually during surgery via the Pochet maneuver (Pallister-Killian? no—correct term: Pringle maneuver) to control bleeding from the liver by occluding blood flow through these structures. The lesser omentum forms the anterior boundary of the omental (epiploic) foramen (of Winslow), which connects the greater and lesser peritoneal sacs; the posterior boundary is the inferior vena cava. Understanding this anatomy is essential for surgical procedures involving the stomach, liver, and biliary tree, as well as for interpreting the spread of ascitic fluid, malignancy, or infection between peritoneal compartments.
Sources
- Moore's Clinically Oriented Anatomy
- Gray's Anatomy for Students
- First Aid for the USMLE Step 1
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