Extrahepatic course of the subsegmental biliary branch of the anteroinferior area of the liver.

Two cases in whom the subsegmental biliary branch of the anterio-inferior area (B5) coursed to the right laterally and inferiorly, forming a caudally convex arc, and running near the neck of the gallbladder are reported. In these two patients, the B5 branches were not aberrant, however, these branches were running near the gallbladder bed extrahepatically, which alerted us to the risk of their inadvertent division. The relationship between the cystic duct and the B5 branch is clinically important during cholecystectomy, especially laparoscopic cholecystectomy.