Absence of the portal bifurcation at the hilum of the liver due to intrahepatic origin of the left branch of the portal vein

Abstract The authors report a rare anomaly of portal vascularization which was detected by CT-scan and MRI and then confirmed surgically. There was no portal bifurcation at the hilum of the liver. After giving off its right dorsal branch, the portal vein entered the right liver and divided in the parenchyma into the right ventral and left branches. The arterio-biliary distribution was normal. Only a few similar cases have been reported. The left branch of the portal vein is reported to have few variations in contrast with the right one, which has many. The venous structure of the liver varies increasingly with the distance from the left umbilical vein. During a right hepatectomy, the possibility of such a vascularization makes it necessary to ensure that the left branch of the portal vein starts upstream before dividing a portal branch entering the right liver.