| Peroral cholangioscopy (POC) permits direct visualization of the biliary tree for diagnostic procedures and provides endoscopic guidance for therapeutic interventions. With technological developments, single operator cholangioscopy system is replacing POC using mother-baby scope system and can be the standard POC system. Recently developed digital version of SpyGlass, SpyGlass DS system provides much improved image quality, integrated optical probe in catheter, channels for separate irrigation and suction, and easy set-up and plug and play function. It has been provided adequate tissue samples for histological diagnosis, and facilitated stone fragmentation as interventions. Direct POC using an ultra-slim upper endoscope has been proposed as another type of single-operator system. Advantages of direct POC using an ultrathin endoscope include its use of conventional endoscopy equipment, its superior images of the biliary tree with large working channel. Direct intraductal visualization with image-enhanced cholangioscopy including narrow band imaging and target biopsy can provide decisive clues for malignant biliary strictures. Therapeutic interventions can be expanded using widen working channel of ultra-slim scope up to 2.2mm. Not only stone fragmentation on direct visualization, metal stenting, tumor ablation therapy including photodynamic therapy, argon plasma coagulation, or radiofrequency ablation can be applied on direct visualization for the palliation of malignant biliary obstruction. In conclusion, with the technical development including scopes and equipment, POC is expected to expand the diagnostic and therapeutic roles for biliary lesions. |
