Background Endoscopic retrograde cholangiopancreatography (ERCP) is currently the method of choice for the postoperative evaluation of suspected bile duct stones seen on intraoperative cholangiogram (IOC); however, the sensitivity of IOC for identifying biliary pathology is unclear, with studies reporting false positive rates between 30% and 60%.

Objective Evaluate the sensitivity of IOC for biliary pathology, using ERCP with sphincterotomy and balloon sweep as gold standard.

Design Retrospective cohort study.

Setting Tertiary medical centre.

Patients 130 consecutive patients (age 51.3±1.7 years, 69.2% women) who underwent ERCP for the evaluation of abnormalities identified on IOC between 2005 and 2013.

Interventions Endoscopic retrograde cholangiopancreatography

Main outcome measurements Sensitivity of IOC, identify predictors of positive postoperative ERCP and ERCP-related complications.

Results ERCP was successful in all 130 subjects. ERCP-related adverse events occurred in six (4.3%) patients, including self-limited post-sphincterotomy bleeding in three (2.3%) and mild post-ERCP pancreatitis in three (2.3%). Overall, 41 (31.5%) patients had normal cholangiogram at time of ERCP. Finding of a filling defect on IOC was the only predictor for the presence of common bile duct stones on postoperative ERCP (OR 3.3, 95% CI 1.0 to 10.8, p=0.05).

Limitations Retrospective study design.

Conclusions Nearly one-third of patients with abnormal IOC had a normal postoperative ERCP. Significant pathology could have been missed in 1/130 patients. Based on these findings, we believe the use of less-invasive diagnostic modalities may be used in place of ERCP in patients with suspected choledocholithiasis on IOC.