Atypical coeliomesenteric anastomosis: The presence of an anomalous fourth coeliac trunk branch.

The presence of more than three coeliac trunk branches is a commonly encountered variant. Literature occasionally describes cases of middle or left colic arteries originating from the celiac trunks or its branches; however, the presence of an anomalous arterial connection between the celiac trunk and both the superior and inferior mesenteric arteries (SMA and IMA, respectively) has yet to be reported. Routine abdominal dissection of a male Caucasian cadaver, revealed the presence of an anomalous fourth arterial branch on the 4-cm long coeliac trunk. The course of this artery was traced, and it terminated by anastomosing with the marginal artery of the mesenteric circulation. The distal termination point of this anomalous fourth coeliac branch was the marginal artery, 5 cm medial of the splenic flexure, anastomosing almost perpendicularly. The diameter of this anomalous artery was comparable with the left gastric artery at their origins. The artery coursed inferiorlaterally toward the splenic flexure, passing immediately posterior to both the pancreas and the splenic vein. The anastomosis point of this artery, near Griffith's Point, is normally considered a watershed region with dual arterial supply from both the SMA and IMA, allowing collateral circulation. This region has a relatively higher susceptibility to irreversible damage in ischemic diseases because of lower perfusion, thus, the anastomosis of atypical coeliac branches represents a rare case for consideration. Awareness of the possibility of embryological variants will minimize the risk of complications in surgical or clinical procedures, and exploration of rare variants will benefit the understanding of vascular embryology.