It is difficult to diagnose neoplastic bile duct lesions (including cholangiocarcinomas) via direct endoscopic evaluation of the bile duct. Most evaluations of biliary lesions have used indirect imaging modalities such as CT, MRI, or ERCP. However, CT and MRI do not yield tissue diagnoses, unlike ERCP, although the diagnostic accuracy for the latter remains unsatisfactory. Recently, remarkable advances in cholangioscopic systems have been made. Of the currently available cholangioscopic systems, the SpyGlass (Boston Scientific Co, Natick, Mass, USA) is a disposable cholangioscope permitting 4-way deflected steering by a single operator. We aimed to evaluate the efficacy of single-operator cholangioscopy (SpyGlass DS II system) to screen for neoplastic bile duct lesions in patients with bile duct stones, which is one of the risk factor of cholangiocarcinoma.
This is the prospective observational study to explore whether the SpyGlass DS II system could be used to screen early-stage neoplastic bile duct lesions in selected patients.