Sigmoid Arteries Flashcards

Explore the sigmoid arteries, their inferior mesenteric origin, mesocolic course, branching patterns, colonic supply, and anastomoses.

Card 1 of 26Question

What are the sigmoid arteries?

Arteries that provide the principal arterial blood supply to the sigmoid colon.

In This Section

1. What are the sigmoid arteries?

Arteries that provide the principal arterial blood supply to the sigmoid colon.

2. From which major artery do the sigmoid arteries typically arise?

The inferior mesenteric artery.

3. Which embryological division of the gastrointestinal tract is supplied by the sigmoid arteries?

The hindgut.

4. How many sigmoid arteries are typically present?

Usually two to four, although the number varies.

5. From which aspect of the inferior mesenteric artery do the sigmoid arteries usually arise?

The left or anterolateral aspect.

6. What is the usual position of the sigmoid arteries relative to the left colic artery?

They generally arise distal to the left colic artery.

7. Within which peritoneal structure do the sigmoid arteries travel?

The sigmoid mesocolon.

8. In which general direction do the sigmoid arteries travel from their origins?

Inferiorly and laterally toward the sigmoid colon.

9. Which intestinal segment receives the principal blood supply from the sigmoid arteries?

The sigmoid colon between the descending colon and rectum.

10. What do the sigmoid arteries form by anastomosing with adjacent branches?

Arterial arcades within the sigmoid mesocolon.

11. What are the vasa recta of the sigmoid colon?

Straight arterial branches extending from mesocolic arcades toward the intestinal wall.

12. Which artery typically anastomoses with the superior sigmoid arterial branches?

The descending branch of the left colic artery.

13. Which artery anastomoses with the lowest sigmoid artery near the rectosigmoid junction?

The superior rectal artery.

14. Which artery is the terminal continuation of the inferior mesenteric artery?

The superior rectal artery.

15. To which longitudinal arterial network do the sigmoid arteries contribute?

The marginal artery of the colon, also called the marginal artery of Drummond.

16. What is the functional importance of anastomoses between adjacent sigmoid arteries?

They provide collateral blood flow between neighboring segments of the sigmoid colon.

17. What is Sudeck's point?

A potential watershed region near the rectosigmoid junction between the last sigmoid artery and superior rectal artery.

18. Why may the rectosigmoid junction be vulnerable to ischemia?

Collateral circulation between the lowest sigmoid and superior rectal arterial territories may be insufficient.

19. Which veins accompany the sigmoid arteries?

The sigmoid veins, which drain into the inferior mesenteric venous system.

20. Where are lymph nodes associated with the sigmoid arteries located?

Along the sigmoid vessels within the sigmoid mesocolon.

21. What is a recognized anatomical variation in the origins of the sigmoid arteries?

Several sigmoid arteries may arise from a shared trunk rather than separately from the inferior mesenteric artery.

22. Which retroperitoneal structure must be protected during dissection of the sigmoid mesocolon?

The left ureter.

23. Why are the sigmoid arteries important during sigmoid colectomy?

Their branches must be controlled while preserving adequate perfusion to the remaining bowel.

24. Why are sigmoid arterial pedicles important during surgery for sigmoid colon cancer?

Regional lymphatic drainage follows these vessels, guiding oncologic lymph node dissection.

25. What can result from interruption of sigmoid arterial branches without sufficient collateral circulation?

Ischemia or infarction of the affected sigmoid colon segment.

26. Why is adequate sigmoid arterial perfusion important when creating a colorectal anastomosis?

Sufficient blood flow supports tissue healing and reduces the risk of anastomotic failure.