Radiological anatomy of the bile ducts based on intraoperative investigation in 250 cases.

Intraoperative cholangiograms were studied in 250 patients. Analysis of the data obtained led to the establishment of a protocol for intraoperative cholangiography aimed at identification of anatomical anomalies and variations. Diagnosis of the latter must be achieved in order to avoid possible intraoperative complications. The common hepatic duct was formed by the junction of the right and left hepatic ducts in 52% of the cases studied. Absence of convergence of the posterior and anterior rami of the right hepatic duct was found in 30% of cases. Anatomical variations of the right sectorial duct system were seen in 12% of cases. Conversely, variations of the left sectorial duct system were rarely seen (2% of cases). Careful examination of the intraoperative cholangiograms led us to suspect certain anatomical variations in close to 1% of cases. These variations included abnormal hepatocystic duct, which if undiagnosed could lead to choleperitoneum or inadvertent ligation of the right hepatic duct. An abnormal hepatocystic duct terminating on the gall bladder was found in one patient. Study of the origin of the common bile duct allowed us to define the mode of termination of the cystic duct (on the right margin of the common hepatic duct in 80% of cases) and to identify a short choledochus in 2% of cases. Finally, variations of the duodenal termination of the common bile duct were studied and reflux into the pancreatic duct was seen in 27% of cases. However, the pathological significance of such reflux was rarely found.