Redefining the collateral system between the superior mesenteric artery and inferior mesenteric artery: a novel classification

Abstract

The aim of this study was to evaluate the arterial collateral vasculature between the superior mesenteric artery and the inferior mesenteric artery (IMA) from a surgical perspective.Method: A total of 107 fresh adult cadavers (94 male) were studied with emphasis on the vascular anatomy of the left colon. Dissections were carried out mimicking the anterior resection technique. The vasculature of the left mesocolon and the collaterals between the superior mesenteric artery and the IMA with respect to their relationship to the inferior mesenteric vein (IMV) were assessed and classified. Collaterals were classified into three different groups: marginal anastomoses (via the marginal = pericolic artery), intermediate mesocolic anastomoses (parallel to the marginal artery but neither adjacent to the IMV nor close to the duodenum) and central mesocolic anastomoses (next to the IMV at the level of the duodenojejunal junction and the lower border of the pancreas).Results: All patients had a marginal anastomosis. However, the marginal anastomosis, as the only anastomosis between the superior and inferior mesenteric arteries at the splenic flexure, was observed in 41 cases (38%). In addition to the marginal artery, intermediate mesocolic anastomoses were found in 49 (46%) and a central mesocolic anastomosis was observed in 17 (16%) of the 107 cases in the splenic flexure mesocolon. It is in this latter variant that collateral vessels can be compromised during ligation/transection of the IMV. Conclusion:This new classification can contribute to a precise mesocolic dissection technique and splenic flexure mobilization and help prevent ischaemic damage to the descending colon.

Cadaveric and CT angiography study of vessels around the transverse colon mesentery

“…On the other hand, cadaver research for colon vessels has been reported. In the cadaver study, in all cases, the splenic flexure was supplied by the marginal artery, and there was no area with poor blood flow [ 36 ]. Improvements in computed tomography quality have enabled the vessel construction to be studied in detail.…”

The vessels around the transverse colon mesentery – An investigation using 44 cadaver specimens and 505 cases in which dynamic computed tomography angiography was performed

“…In the cadaver study, in all cases, the splenic exure was supplied by the marginal artery and there was no area with poor blood ow. (33) Improvements in computed tomography quality have enabled the vessel construction to studied in detail.…”

Applied surgical anatomy is back (has it ever left?)

“…For a colorectal surgeon, it is not sufficient to have basic knowledge of this discipline and an optimal level must be required. The paper published by Kuzu et al [1] in the present edition of Colorectal Disease highlights once again the importance of advances in this field. Vascular variability in the colonic splenic flexure is high and its classification and standardization will help during surgical procedures as well as planning future prospective studies.…”

“…Vascularization of this area depends on the embryological union of the superior and inferior mesenteric vessels by means of vascular arches [1]. To perform a total mesocolic excision for a neoplasia of the colonic splenic flexure, all the arches should be included in the specimen considering the possible presence of metastatic lymph nodes along all of them.…”