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Preduodenal portal vein in the adult.

We present three cases of preduodenal portal vein in adult people, which were diagnosed in our department. All of them were identified during elective operation for cholelithiasis, caused some technical difficulties to the performance of the operation, but led to no major intraoperative or postoperative complications. None of them had any preoperative symptoms, which could be related to this anomaly. The preduodenal portal vein is a rare congenital anomaly, which is usually discovered in infants or children due to the obstruction of the duodenum. In adults, it is often asymptomatic, and is usually discovered as an accidental finding during laparotomy for other reason. The postcontrast CT can set the diagnosis, when this anomaly is suspected. Despite its rarity, this anomaly is of great surgical importance, because it can predispose to intraoperative complications including hemorrhage from the abnormal vein, or damage to the biliary tract or the distented duodenum. The anterior position of the portal vein results from the persistence of the ventral anastomosis between the two vitelline veins and the distal portion of the right vitelline vein, with subsequent atrophy of the cranial part of the left vitelline and dorsal anastomotic vein.