Anatomical variations of liver blood supply in patients with pancreaticobiliary maljunction

Purpose Pancreaticobiliary maljunction (PBM) arises from a developmental abnormality during the embryonic period; thus, these patients may have anatomical variations of the liver blood supply, including aberrant vessels and unusual locations. Methods We reviewed retrospectively the vascular anatomy of 52 patients with PBM, who were seen between 1998 and 2013. Results There were 11 male patients and 41 female patients. Sixteen patients had bile duct type (C–P type) PBM, 35 had pancreatic duct type (P–C type) PBM, and one had complex type PBM. Thirty-three patients had biliary dilatation. Nine (17.3 %) patients had an aberrant (replaced or accessory) hepatic artery and 2 (3.8 %) had an aberrant portal vein. Among 39 patients evaluated by contrast-enhanced computed tomography, 8 (20.5 %) had their right hepatic artery positioned on the ventral side of the common bile duct. The presence of aberrant hepatic vessels was not related to the type of confluence, biliary dilatation, type of Todani classification, or associated biliary malignancies. Conclusions The incidence of the right hepatic artery being located on the ventral side of the common bile duct may be higher in patients with PBM than the naturally occurring incidence of about 10 % in the general Japanese population.