Visualization of the bile ducts using focused ultrasound.

The feasibility of using focused ultrasound for studying structures as small as biliary ducts and correlative radiological and ultrasonic studies of the common and larger hepatic ducts are presented. Patients whose bile ducts were visualized on intravenous or T-tube cholangiography or oral cholecystography underwent radiography with a metallic skin marker along the right anterior lower costal margin. The marker was then correlated with ultrasonic observations of multiple oblique scans parallel to the lower costal margin. The common duct could be identified in 15 of 21 patients. Ultrasonic visualization circumvents the problems of elevated serum bilirubin, iodine contrast media sensitivity, and pregnancy.