Anomalous duplicated cystic duct as a surgical hazard: report of a case.

Anomalies of the biliary ductal system are not uncommon, and their clinical significance is variable. We present herein the case of a 70-year-old Japanese woman found to have an anomalous duplicated cystic duct, which is an extremely rare congenital anomaly. Intraoperative delineation of the anomaly by real-time cholangiograms assisted us in being able to subsequently perform a safe cholecystectomy. This case serves to demonstrate the importance of being aware of the possibility of potential biliary variations in order to avoid ductal injuries during biliary surgery.