Evaluation of residual bile duct stones by peroral cholangioscopy in comparison with balloon-cholangiography.

We evaluated the usefulness of peroral cholangioscopy (POCS) for residual bile duct stones in patients with complete bile duct clearance confirmed by balloon-occluded cholangiography. A total of 108 patients with common bile duct stones who underwent POCS after extraction of stones via endoscopic sphincterotomy, resulting in complete bile duct extraction confirmed by balloon-occluded cholangiography, were retrospectively evaluated. For the treatment of difficult stones, stones were fragmented by mechanical lithotripsy (ML) or electrohydraulic lithotripsy (EHL). In 26 patients (24%), residual stones were detected with POCS in the lower bile duct. In patients with residual stones, large bile duct stones, juxtapapillary diverticulum, and use of ML or EHL were significantly related to residual stones (P < 0.05). Although a prospective study is necessary to clarify whether this procedure is appropriate in aspects of cost and benefits, POCS appears to be a useful diagnostic tool for confirming complete extraction of bile duct stones. POCS may be useful, particularly when lithotripsy using ML or EHL is performed and a large pneumobilia exists in the bile duct.