Anatomy of Inferior Mesenteric artery: A cadaveric study

Abstract

Introduction: A comprehensive knowledge of the varied anatomy of the inferior mesenteric artery (IMA) can be important in surgeries in the region of the colon and rectum. Methods: We analyzed 50 fresh cadavers in the department of Anatomy, Faculty of Medicine Ragama from 2022 to 2024. Latarjet’s classification was used for the IMA branching pattern. The anatomical relationships of the IMA left colic artery (LCA), sigmoidal artery (SA), and superior rectal artery (SRA) were observed, and the length from the origin of the IMA to the point of branching into the LCA or common trunk of LCA and SA was measured. The relationship between LCA and inferior mesenteric vein (IMV) was also observed. The data was presented as the value / percentage. Results: Majority showed Type A branching pattern 35/50 (70%). The respective lengths from the origin of the IMA to the beginning of LCA were measured and expressed as (mm) (mean ± SD) for each type; Type A 33.4 ± 4.7, Type B 36.5 ± 5.4, Type C 39.2 ± 8.6. The number of LCA under IMV in type A (51%); type B (54%); type C (62%) respectively. There was no statistically significant difference among the three types. Conclusion: Our study showed that type A branching pattern of LCA was the commonest. It is also observed that almost similar incidence of LCA traversing above and beneath the IMV.