Electrohydraulic Lithotripsy for Difficult Bile Duct Stones under Endoscopic Retrograde Cholangiopancreatography and Peroral Transluminal Cholangioscopy Guidance

Electrohydraulic lithotripsy (EHL) under endoscopic retrograde cholangiopancreatography (ERCP) guidance can be an option to treat difficult stones. Recently, a digital, single-operator cholangioscope (SPY-DS) has become available. Peroral transluminal cholangioscopy (PTLC) using SPY-DS has also been reported. In this retrospective study, the technical feasibility and clinical effectiveness of EHL for difficult bile duct stones under ERCP guidance and under PTLC guidance was examined. In this pilot study, patients with difficult bile duct stones between July 2016 and July 2017 were retrospectively enrolled. Forty-two consecutive patients underwent EHL using a SPY-DS; 34 patients underwent EHL under ERCP guidance, and the other 8 patients underwent EHL under PTLC guidance. Median procedure time was 31 min (range 19 to 66 min). The median number of EHL sessions was 1 (range 1 to 2), and that of ERCP sessions was also 1 (range 1 to 3). The rate of complete stone clearance was 98% (41/42). Adverse events such as cholangitis and acute pancreatitis were seen in 14% (6/42), which could be treated conservatively. EHL using SPY-DS was technically feasible, not only under ERCP guidance, but also PTLC guidance. A prospective clinical study of EHL using SPY-DS is needed.