Laparoscopic ultrasonography versus intra-operative cholangiogram for the detection of common bile duct stones during laparoscopic cholecystectomy: a meta-analysis of diagnostic accuracy.

BACKGROUND Routine intra-operative cholangiography (IOC) during laparoscopic cholecystectomy is often not performed because of increased operative time, radiation, and failure rate. Laparoscopic ultrasound (LUS) is a less invasive alternative but studies comparing it to IOC have been of small sample size. This study aims to assess the diagnostic accuracy of LUS in detecting common bile duct (CBD) stones compared to IOC. METHODS This meta-analysis was executed and reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta- Analyses (PRISMA) statement. 11 comparative studies (1994-2013) reporting on 12 patient groups were included. A bivariate model for diagnostic meta-analysis was used to attain overall pooled sensitivity and specificity for IOC and LUS, and their relationship assessed using a hierarchical summary receiver operating characteristic model with meta-regression. RESULTS IOC had a pooled sensitivity of 0.87 (95% CI 0.77-0.93) and a pooled specificity of 0.99 (95% CI 0.98-0.99) with no significant heterogeneity. The diagnostic Odds Ratio (OR) was 442 (95% CI 196-997) and pooled weighted Area Under the Curve (AUC) was 0.99 (95% CI: 0.98-1.0). LUS had a pooled sensitivity of 0.87 (95% CI 0.80-0.92) and a specificity of 1.00 (95% CI 0.99-1.00). Heterogeneity was significant for specificity results. The diagnostic Odds Ratio (OR) was 1171 (95% CI 372-3689) and the pooled, weighted AUC was 1 (95% CI: 0.99-1). Meta-regression did not identify factors that significantly predict diagnostic accuracy. CONCLUSIONS LUS is a potentially useful imaging modality to confirm the absence of CBD stones without needing to cannulate the biliary system.