[Evaluation of anomalous bile ducts using helical CT cholangiography]

To evaluate the usefulness of helical CT cholangiography (DIC-CT) for laparoscopic cholecystectomy.

Prior to laparoscopic cholecystectomy, 151 patients were examined by DIC-CT. DIC-CT was performed 30 minutes after drip infusion of 100 ml of Iotroxic acid meglumine. Two-dimensional axial (2D) images with 2.5 mm or 1.5 mm slice thickness were reformatted from the raw data, and three-dimensional (3D) images were reconstructed using the surface reconstruction method. Two- and three-dimensional images were compared with the operative cholangiograms in all subjects.

DIC-CT images of 16 cases of aberrant bile duct (10.6%) and 4 cases of anomalous junction of the cystic duct (2.6%) corresponded to the operative cholangiogram. In one case of an aberrant posterior bile duct, which drained into the common bile duct more proximally to the papilla Vater than the cystic duct did, it was difficult to diagnose correctly the anomalous junction of the bile duct on 2D images but easy on 3D images. Although another case was misdiagnosed to have double cystic ducts on 3D images, the 2D images and operative cholangiogram showed normal junction of a cystic duct.

Both 2D and 3D images were useful and necessary in the evaluation of anomalous bile ducts before laparoscopic cholecystectomy.