Abstract
“The low union hepatic duct” implies mainly the one traditionally called accessory or aberrant hepatic duct, but it includes the main right and left hepatic ducts joining at low position. In this study the incidence of anomalous union of this low union hepatic duct with the cystic duct and the hepatic portions drained by the low union hepatic ducts concerned in this anomaly were examined in 857 patients who underwent operative procedures for the extrahepatic bile duct system. The incidence of the anomaly in which the cystic duct drained into the low union hepatic duct was 1.5% and of the anomaly in which the low union hepatic duct drained into the cystic duct was 0.6%. The hepatic portions drained by these low union hepatic ducts were all right lobe and the extent of the hepatic portion varied from subsegment to all right lobe. These results indicate that it is natural to consider that both the extrahepatic bile duct anomaly called accessory or aberrant hepatic duct and the one in which the main right and left hepatic ducts join at low position belong to the same category.
