Diagnostic and therapeutic peroral cholangioscopy

Abstract

Peroral cholangioscopy (POC) provides direct visualization of the bile duct and facilitates diagnostic or therapeutic intervention. The currently available single-operator POC systems are "Mother-baby" scope system, SpyGlass direct visualization system, and direct POC using a regular ultra-slim upper endoscope. Direct POC using an ultra-slim upper endoscope having a larger 2-mm working channel can provide a valuable and economic solution for evaluating bile-duct lesions. Main diagnostic procedures under direct POC are visual characterization and optically guided target biopsy for the indeterminate bile duct lesion. Image-enhanced endoscopy such as narrow-band imaging has shown promise for more detailed evaluation of mucosal abnormality and can be performed under direct POC. Intracorporeal lithotripsy such as electrohydraulic lithotripsy or laser lithotripsy is a main therapeutic intervention of direct POC for patients with bile duct stones that are resistant to conventional endoscopic stone-removal procedures. Besides, tumor ablation therapy, such as photodynamic therapy and argon plasma coagulation may be also performed using direct POC. Further developments of the endoscope and specialized accessories or devices are expected to facilitate diagnostic and therapeutic role of this cholangioscopic procedure.