Arterial anomaly of crucial importance in resection of head of pancreas.

In a patient with pancreatic cancer, an arterial anomaly was observed that apparently consisted of the congenital absence of the celiac axis and the replacement of the pancreaticoduodenal arcade by an anomalous vessel. The complete or near-complete arterial flow to the liver and spleen depended upon this anomalous prepancreatic vessel that arose from the superior mesenteric artery. The anomaly was demonstrated preoperatively by arteriography. At laparotomy, the anomalous artery was prominent, lying across the surface of the head of the pancreas. Unrecognized, its operative interruption might have threatened the life of the patient. Resection of the head of the pancreas would have required restoration of the arterial flow, preferably by vascular grafting. The anomaly appears to be different from those previously described.