Inter-mesenteric connections between the superior and inferior mesenteric arteries for left colonic vascularization: implications for colorectal surgery.

Purpose: There is confusion regarding the names, the number, and the exact location of the colonic arterial arches which provide connections between the superior and inferior (IMA) mesenteric arteries at the level of the left colic angle. The aim of this review was to delineate the "true" colic arches arising in the meso of the left colic angle and to describe their surgical implications.

Methods: A systematic review of the literature was performed using the MEDLINE database. The search included only human studies between 1913 and 2018. All dissection, angiographic, arterial cast and corrosion studies were analyzed.

Results: The terms "Riolan arch", "marginal artery of Drummond", "meandering mesenteric artery" and "Villemin's arch" must no longer be used in the scientific literature. Three arterial arches were found at the level of the left colic angle, permitting the communication between the two arterial mesenteric systems: (1) the Marginal Artery (the most peripheral, found in 100% of cases); (2) the "V" termination of the ascending branch of the left colic artery (LCA), existing in more than 2/3 of cases; and (3) the inter-mesenteric trunk, found more centrally located and existing in less than 1/3 of cases.

Conclusions: Three arterial arches exist at the level of the left colic angle: (1) the Marginal Artery, (2) the "V" termination of the ascending branch of the LCA, and (3) the inter-mesenteric trunk. The knowledge of this anatomy is essential for performing colorectal surgeries involving ligation of the IMA.