Ultrasonic indications to explore the common bile duct.

A prospective comparison between operative cholangiography and operative choledochosonography has been made in 100 patients with cholelithiasis and potential choledocholithiasis. Thirty-one common bile ducts were explored, and 25 of them contained stones. Operative cholangiography was attempted in every case, but technical difficulties prevented examination of 12 common bile ducts, two of which contained stones. Both of these stones were detected by operative ultrasonography. Of the remaining 88 ducts, the sensitivity of the operative cholangiogram was 96% and the specificity 96%. Operative ultrasonography was performed for all 100 patients, with a sensitivity of 96% and a specificity of 93%. The ultrasonic findings of a sonically dense particle, shadowing, dilatation of the duct, and the persistence and meniscus signs are described with their relative incidence in the 100 patients. The time required for choledochosonography (3 to 5 minutes) compared favorably with the time needed for operative cholangiography (10 to 15 minutes). Operative bile duct scanning is a rapid, reliable technique for detecting the presence of choledocholithiasis at the time of routine cholecystectomy.