Carbon dioxide insufflation vs. conventional saline irrigation for peroral video cholangioscopy

Background and study aims: Recent studies have evaluated the efficacy of peroral cholangioscopy (POCS) for diagnosis of biliary diseases. In order to obtain clear images with POCS, saline irrigation, which is performed to replace yellow bile, is carried out for an extended duration. The aim of this study was to evaluate the feasibility of replacing saline irrigation with CO(2) insufflation during POCS. Patients and methods: A total of 36 patients who had bile duct lesions and were due to undergo POCS were enrolled in the study. Of these patients, 18 underwent POCS using saline irrigation followed by CO(2) insufflation, and 18 patients underwent the reverse approach. The two methods were compared with regard to the time required to obtain a clear endoscopic image and the quality of the images. Results: The median time required to obtain a clear endoscopic image using CO(2) insufflation (5.0 min) was significantly shorter than that required for saline irrigation (22.5 min; P < 0.001). The quality of the endoscopic images obtained was similar in 27 cases. However, CO(2) insufflation provided better images in four cases that showed an abundance of mucin or biliary sludge, and saline irrigation was superior to CO(2) insufflation in five cases that showed severe stricture with bleeding and tall papillary lesions. Conclusions: CO(2) insufflation during POCS can reduce procedure time and simplify cholangioscopy. The overall image quality was similar to that obtained with conventional saline irrigation.