Variations in the branching pattern in inferior mesenteric artery: a series of five cases

Abstract

Introduction: Inferior mesenteric artery arises from abdominal aorta just below the third part of duodenum at the level of L3-L4 vertebra. It supplies left colon and rectosigmoid colon through its branches namely- left colic artery, two-three sigmoid arteries and superior rectal artery. The branching pattern of inferior mesenteric artery is of immense use in colon surgery. Material and Methods: The study was carried out in the department of anatomy by dissecting seven embalmed cadavers. The inferior mesenteric artery and its branches were identified; its vertebral level was analysed. The length and diameter of inferior mesenteric artery were measured by vernier callipers. Results: In first case, bifurcation of inferior mesentric artery into common trunk and main artery then trifitrcation of main artery and bifurcation of common trunk belong to anomalous configuration. In second case, this artery gave a tetrafitrcated common trunk and main artery which continued as superior rectal artery. In third case, the same artery trifurcated into left colic, superior rectal artery and bifurcated common trunk. In fourth case, the artery bifurcated into common trunk further dividing into left colic and sigmoid arteries and main artery into superior rectal and sigmoid arteries. In fifth case, this artery trifitrcated into three branches namely, sigmoid, rectosigmoid, and superior rectal arteries. Left colic artery arose from superior mesenteric artery. Conclusion: The knowledge of branching pattern of inferior mesenteric artery will be of paramount importance to colon surgeons during colectomy, to radiologists in avoiding misinterpretation of radiographs and anatomists for new variants.

Keywords

colon - inferior mesenteric artery - rectum - sigmoid artery