Diagnosis of asymptomatic common bile duct stones: preoperative endoscopic ultrasonography versus intraoperative cholangiography--a multicenter, prospective controlled study. French Associations for Surgical Research.

BACKGROUND: In patients with symptomatic cholelithiasis, preoperative diagnosis of common bile duct (CBD) stones can modify the therapeutic strategy. The aims of this prospective, controlled multicenter study were to assess the feasibility, concordance, discordance, and indexes such as sensitivity, specificity, positive and negative predictive values, and accuracy of preoperative endoscopic ultrasonography compared with those of intraoperative cholangiography (IOC) in the diagnosis of asymptomatic CBD stones (i.e., patients undergoing cholecystectomy with no clinical or biologic evidence of CBD stones).

METHODS: From October 1993 to October 1995, 240 consecutive patients with symptomatic cholelithiasis, scheduled for cholecystectomy in 14 surgical centers, were enrolled in this study. All patients were selected for this study according to a preoperative high-risk CBD stone predictive score. Each patient underwent both endoscopic ultrasonography and IOC, as well as surgical exploration of the CBD when stones were detected during one or both preoperative investigations. All patients were seen 1 months and 1 year after operation to check for residual stones.

RESULTS: The feasibility of endoscopic ultrasonography was significantly higher overall than that of IOC (99% vs 90%; p < 0.001), except when IOC was through a laparotomy (97% vs 93%; p = 0.16). The number of patients available for study was 215. In 198 cases (92%), results of both investigations were in concordance (161 negative and 37 positive values). Seventeen cases (8%) were discordant. There was overall concordance between the two investigations (kappa coefficient 0.764; 95% confidence interval 0.66 to 0.87), but the percentage of discordance was in favor of IOC. Sensitivity and specificity of IOC were significantly higher than those of endoscopic ultrasonography (1.00 and 0.98 vs 0.85 and 0.93, respectively). With a prevalence of CBD stones of 19%, positive and negative predictive values of IOC were significantly higher than those of endoscopic ultrasonography (0.93 and 1.00 vs 0.75 and 0.96, respectively).

CONCLUSIONS: Although endoscopic ultrasonography is feasible more often than IOC, IOC is associated with a slightly lower degree of discordance and better information indexes and remains an efficient method of investigation for CBD stones. Endoscopic ultrasonography can be suggested in preference to endoscopic retrograde cholangiography when postoperative residual stones are suspected but need not be performed routinely before cholecystectomy.