Course and Variations in Branches of Inferior Mesenteric Artery

Abstract

Background : The mesenteric blood supply is a combination of rich collateral networks. There are frequent anatomical variants encountered and these variations are sometimes involved in pathologies. Treatment of which requires a better understanding of the variations in the normal anatomy of the inferior mesenteric artery. Methods : The present study was carried out in the Department of Anatomy, Prathima Institute of Medical Sciences, Karimnagar. A total of n=50 specimens, with n=17 adult males and n=2 adult female cadavers and fetuses of which n=26 were term and n=2, was preterm. Female fetuses n=2 of term and n=1 preterm were included in the study. Results : The following variations were observed in the present study of course and variations in the branches of the inferior mesenteric artery and are grouped into three types. Type I: In this type middle colic artery is arising from the inferior mesenteric artery instead of the superior mesenteric artery. It is a rare-variations and observed in a female fetus. Type-II: Four Sigmoidal arteries are arising from an inferior mesenteric artery, after the origin of the left colic artery. This type is observed in a male fetus. Type-III: Three Sigmoidal arteries are originated from the inferior mesenteric artery. This type was observed in a male adult and a male fetus. Conclusion: Out of the 50 cases included in the study we found type 1 variation of IMA in 2% of cases, type 2 variation was found in 2% samples, and type 3 variation was found in 4% of samples. Based on the variations radiologists and Surgeons should be aware of possible consequences when doing colectomy, right hemicolectomy, left hemicolectomy, sigmoidectomy, en-bloc resection of the head of the pancreas, aneurysm, and chronic bowel ischemia. The present study is also useful for reconstructive surgeries in inferior mesenteric arteries in the case of ischemia.