Anatomic relationship of intrahepatic bile ducts to portal veins

To assess the anatomic relationship between the intrahepatic bile ducts and corresponding portal veins, we studied anterior-posterior relationship of the segmental bile ducts to the accompanying portal veins using sonograms and cadavers. On sonograms of the 64 segments in 16 patients with biliary dilation, the segmental bile ducts lay anterior to the corresponding portal veins in 34%, posterior in 39%, superior in 2%, tortuous in 13%, and undetermined in 13%. The relationship was inconsistent in terms of hepatic segments and thus bile ducts lay anterior to the portal vein in one segment and posterior in the other segment within the same liver. Sagittal sections in 11 segments of the 3 cadaveric livers revealed that the bile ducts were anterior to the corresponding portal veins in 1 segment, posterior in 2 segments, superior in 5 segments, anterosuperior in 1 segment, and posterosuperior in 2 segments. It is concluded that, contrary to the common belief, there is no constant anterior-posterior relationship between the intrahepatic bile ducts and the corresponding portal veins.