A Preliminary Study on the Efficacy of Single-Operator Cholangioscopy with a New Basket for Residual Stone Retrieval After Mechanical Lithotripsy

Background and Aim The detection of residual or fragmented common bile duct (CBD) stones after lithotripsy can be improved by the high-resolution imaging quality of digital, single-operator cholangioscopy (SOC). However, therapeutic interventions for the removal of residual CBD stones are limited by the lack of appropriate tools. We retrospectively evaluated the role of SOC and the newly developed Dormia basket for the evaluation and removal of stones remaining after lithotripsy. Methods Thirty-four patients who had undergone lithotripsy for retained CBD stones with no evidence of filling defects in occluded balloon cholangiography from March 2017 to October 2018 were included in the study. After balloon cholangiography, the bile duct was evaluated by SOC for complete evacuation of the stones. The detected residual CBD stones were directly retrieved by inserting the newly developed Dormia basket into the working channel of the SOC. The incidence of residual stones detected by SOC and the success rate of residual stone retrieval by SOC were investigated. Results Digital SOC was successfully performed in all patients. Of these, 11 patients (32.4%) had residual CBD stones. The residual stones were successfully removed in 10 patients (90.9%) by SOC using the Dormia basket, except in one case of residual stones left in the hepatic duct. There were no adverse events associated with the SOC procedures or direct stone removal. Conclusions Digital SOC combined with the newly developed Dormia basket was useful for the detection and extraction of residual CBD stones under direct visualization after lithotripsy.