Value of endoscopic ultrasonography in the diagnosis of common bile duct stones: comparison with surgical exploration and ERCP.

An accurate and safe preoperative method of imaging the common bile duct is essential for the proper diagnosis of calculous biliary tract disease, especially in the current era of laparoscopic cholecystectomy. The value of endoscopic ultrasonography in detecting common duct stones has been reported, albeit in small series. The aim of this retrospective study was to assess the accuracy of EUS in a large series of patients. We compared EUS to direct cholangiography in the evaluation of 422 patients for common duct stones. Ductal stones were imaged by EUS in 168 patients (43.4%). No complications were encountered. EUS failed in 2.3% of cases, ERCP failed in 8.3%, and surgical exploration failed in 0.5%. Comparison of EUS with surgical exploration in 185 patients showed a sensitivity of 94.9%, a specificity of 97.8%, and an accuracy of 95.9%. EUS was compared to ERCP in 219 patients. All common duct stones found by ERCP were evident by EUS. Concordance was obtained in 91.3% of cases. Review of videotapes disclosed 3 false-positives and 16 unequivocal true-positives. We conclude that EUS is a safe and highly accurate means of detecting common duct stones and should be proposed before laparoscopic cholecystectomy in patients at risk of choledocholithiasis.