Double barrelled common bile duct: a threat to biliary surgery.

The frequency of cholecystectomies has given the surgeon familiarity and confidence when dealing with biliary anomalies. Internal anomalies are not equally recognized, for they play little role in cholecystectomy. Recognition of internal anomalies is of prime importance, however, when the biliary tree is drained through the gallbladder. Radiographic confirmation of a patent drainage system, avoiding spillage of contrast material, should be routinely employed in these situations to obviate potentially lethal complications due to technical error.