Appearance of the gallbladder and biliary tree by CT cholangiography

The computed tomographic (CT) cholangiographic appearance of the gallbladder and bile ducts was retrospectively analyzed in 121 patients undergoing routine abdominal CT. The entire course of the common duct was visualized in 106 cases (88%). From this group, 100 (94%) patients had ducts that coursed in a parasagittal or oblique plane, and six patients (4%) had ducts with a horizontal course. Opacification of the gallbladder was observed in 102 patients (83%), with the majority (80 patients) demonstrating a homogeneous appearance. Different patterns of inhomogeneous opacification are described. Signs of cholelithiasis or cholecystitis include: a filing defect in an opacified gallbladder, a focal density in a faintly opacified gallbladder, or the indirect sign of a nonopacified gallbladder with an opacified bile duct.