Efficacy of endoscopic ultrasound after removal of common bile duct stone

Objective: Endoscopic retrograde cholangiopancreatography (ERCP) is a standard procedure for choledocholithiasis. Nonetheless, the recurrence rate remains quite high. This study aimed to investigate the prevalence and related factors of remnant biliary stone or sludge using endoscopic ultrasound (EUS) after the removal of common bile duct (CBD) stone and to evaluate the long-term clinical outcomes. Methods: A prospective study enrolling a consecutive series of patients who underwent ERCP for CBD stone removal was performed between June 2014 and November 2015. Following confirmation of complete CBD stone removal by the operator, EUS was performed to determine whether biliary stone or sludge remained. Patients underwent cholecystectomy if a gallstone was identified and were subsequently followed up at a regular interval of 3-6 months. We investigated whether symptomatic recurrence would occur. Results: A total of 130 patients were enrolled. The presence of remnant biliary stone or sludge after ERCP was confirmed in 36.9% (48/130) of patients. Acute angulation of the distal CBD was the sole factor associated with remnant biliary stone or sludge (p < .01). During the follow-up period, the overall recurrence rate was 17.7% (23/130). Recurrent symptomatic choledocholithiasis was predicted by remnant biliary sludge and large CBD diameter in multivariate analysis. Conclusions: Acute angulation of the distal CBD was associated with remnant biliary stone or sludge after ERCP. Remnant biliary sludge on EUS and large CBD diameter were strong predictors of symptomatic recurrence. EUS evaluation following CBD stone removal could be an effective strategy in the treatment of choledocholithiasis.