Lesser Sac (Omental Bursa) Flashcards

Examine the lesser sac, its anatomical boundaries, peritoneal recesses, communications, and relationships with nearby organs.

Card 1 of 24Question

What is the lesser sac?

A peritoneal compartment located primarily posterior to the stomach and lesser omentum.

In This Section

1. What is the lesser sac?

A peritoneal compartment located primarily posterior to the stomach and lesser omentum.

2. What is another anatomical name for the lesser sac?

The omental bursa.

3. Which opening connects the lesser sac with the greater sac?

The epiploic foramen, also called the foramen of Winslow.

4. What forms the anterior boundary of the main portion of the lesser sac?

The posterior surface of the stomach and the lesser omentum.

5. Which major retroperitoneal organ lies posterior to the lesser sac?

The pancreas.

6. What forms the posterior wall of the lesser sac?

Parietal peritoneum covering the pancreas and adjacent posterior abdominal structures.

7. Which part of the liver is closely related to the superior recess of the lesser sac?

The caudate lobe.

8. Which structure limits the inferior extent of the main lesser sac cavity in adults?

The transverse mesocolon and the fused layers of the greater omentum.

9. Which organ lies at the left end of the lesser sac?

The spleen.

10. Which two peritoneal ligaments form the left boundary of the lesser sac?

The gastrosplenic and splenorenal ligaments.

11. What are the three commonly described recesses of the lesser sac?

The superior, inferior, and splenic recesses.

12. Where does the superior recess of the lesser sac extend?

Upward between the caudate lobe of the liver and the diaphragm.

13. Where does the inferior recess of the lesser sac extend during development?

Downward between the layers of the greater omentum.

14. What normally happens to the inferior recess of the lesser sac during development?

It becomes largely obliterated as the layers of the greater omentum fuse.

15. Where is the splenic recess of the lesser sac located?

Between the gastrosplenic and splenorenal ligaments near the splenic hilum.

16. Which part of the lesser omentum forms the anterior boundary of the epiploic foramen?

The hepatoduodenal ligament.

17. Which major blood vessel forms the posterior boundary of the epiploic foramen?

The inferior vena cava, covered by peritoneum.

18. Which embryological structure gives rise to the lesser sac?

The peritoneal recess formed by rotation of the stomach and displacement of the dorsal mesogastrium.

19. What is the anatomical relationship between the lesser sac and the posterior gastric wall?

The lesser sac separates the posterior gastric wall from the pancreas and posterior abdominal structures.

20. Which peritoneal ligament contains the short gastric vessels along the left boundary of the lesser sac?

The gastrosplenic ligament.

21. Which peritoneal ligament contains the splenic vessels and the tail of the pancreas?

The splenorenal ligament.

22. Why is the lesser sac clinically important in pancreatitis?

Inflammatory fluid and pancreatic collections can accumulate within the lesser sac.

23. How can a surgeon gain access to the lesser sac through the greater omentum?

By dividing the gastrocolic ligament between the stomach and transverse colon.

24. Which gastric surface may be approached surgically through the opened lesser sac?

The posterior surface of the stomach.