Background: Clinical implementation of cholangioscopy for direct visual examination of bile ducts, tissue sampling, and therapeutic maneuvers has been slowed by limitations in available technology. With 4-way deflected steering and dedicated irrigation channels, the single-operator SpyGlass peroral cholangiopancreatoscopy system is designed to overcome some of these limitations.
Objective: To evaluate the clinical utility and safety of the SpyGlass system for diagnostic and therapeutic endoscopic procedures in bile ducts.
Design: Prospective observational clinical feasibility study.
Setting: Two tertiary referral centers.
Main outcome measurements: Procedural success rate defined as the proportion of SpyGlass procedures in which the diagnostic or therapeutic objectives of the procedure were achieved.
Results: SpyGlass procedures were performed in 35 patients: 22 with indeterminate strictures (63%), 5 with indeterminate filling defects (14%), 5 with stones (14%), 2 with cystic lesions (6%), and 1 patient with an indication for gallbladder stent placement (3%). The rate of procedural success was 91% (95% confidence interval 77%-98%). Twenty patients underwent SpyGlass-directed biopsy, and the specimens procured from 19 patients (95%) were found adequate for histologic evaluation. The preliminary sensitivity and specificity of SpyGlass-directed biopsy to diagnose malignancy were 71% and 100%, respectively. SpyGlass-directed electrohydraulic lithotripsy succeeded in 5 of 5 patients (100%). Procedure-related complications occurred in 2 patients (6%) and resolved uneventfully.
Limitations: No control group was included. Follow-up for determining preliminary sensitivity and specificity was limited.
Conclusions: SpyGlass procedures proved to be clinically feasible, provided adequate samples for histologic diagnosis, and successfully guided stone therapy. The procedures were safe and well tolerated. Prospective multicenter clinical trials of the system are underway.