Noninvasive imaging of the biliary tree before or after laparoscopic cholecystectomy: use of three-dimensional spiral CT cholangiography.

Abstract
The purpose of this study was to determine the feasibility of using three-dimensional spiral CT after IV administration of a cholangiographic agent for noninvasive detection of anatomic variations of the bile ducts and common bile duct stones before or after laparoscopic cholecystectomy. Three-dimensional spiral CT cholangiography was performed before laparoscopic cholecystectomy in 24 patients and after surgery in two patients who had recurrent symptoms. After slow infusion of 250 ml of iodipamide, spiral CT was performed. Three-dimensional images of the bile ducts and a secondary reformation through the long axis of the common bile duct were obtained. Visualization of the biliary tract was evaluated by two observers. Detection of anatomic variations and common bile duct stones was assessed in 19 patients for whom a gold standard (operative or retrograde cholangiogram) was available. In all 26 patients, the common bile duct and the confluence of the hepatic ducts were seen on three-dimensional spiral CT cholangiograms, and in 21 patients second- or higher-order branches were also seen. Seven patients had anatomic variations and two had common bile duct stones. These anomalies were proved by operative cholangiography in each case, except for a low junction of the cystic duct and a common bile duct stone, which were shown by retrograde cholangiography. Six of the seven anatomic variations were adequately detected with spiral CT cholangiography, as were the two cases of common bile duct stones. Three-dimensional spiral CT cholangiography is a feasible method for noninvasive detection of biliary anatomic variations and common bile duct stones before or after laparoscopic cholecystectomy.