Intersegmental arterial communication between the medial and left lateral segments of the liver.

BACKGROUND/AIMS Although the interlobar arterial collateral of the liver has been thoroughly analyzed, few reports have described the intersegmental arterial collateral between the medial and left lateral segments. METHODS The hepatic arterial system of the left liver was evaluated using 12 latex resin cast specimens in which latex resin was injected into the left hepatic artery after ligation of the right hepatic artery. RESULTS In all 12 livers, an intersegmental collateral between the medial and left lateral segments was detected. These collaterals were extrahepatically located in the umbilical plate and gave rise to branches traveling to the bile duct of the left liver. CONCLUSIONS The present study showed that the communicating arcade between the middle and left lateral hepatic arteries was consistently present in the umbilical plate and played an important role not only in the intersegmental arterial collateral system of the left liver but also in the blood supply to the bile ducts.