Carbon dioxide insufflation is useful for obtaining clear images of the bile duct during peroral cholangioscopy (with video)

Background: Peroral cholangioscopy (POCS) is useful for the diagnosis of various bile duct lesions. However, it is often difficult to obtain clear images because of bile or biliary sludge in the bile duct, even after vigorous irrigation of the bile duct with saline solution. Therefore, this study investigated whether inflation with carbon dioxide (CO₂) yields clearer images of the bile duct than conventional saline solution irrigation during POCS. Objective: To evaluate the clinical utility and safety of CO₂ insufflation into the bile duct to obtain clear images in POCS observations by comparing this method with conventional saline solution irrigation. Setting: A single center. Design: Case-control study. Patients: Nineteen patients with suspected biliary diseases. Interventions: CO₂ insufflation into the bile duct during POCS. Main Outcome Measurements: The quality and safety of this method. Result: The quality of the images of the bile duct lumen with CO₂ insufflation (10 patients) was significantly superior to those with saline solution irrigation (9 patients) in both clarity (P < .05) and color (P < .05). In particular, extremely clear images could be obtained from the middle part of common bile duct to the right and left hepatic duct. No serious POCS-related complications occurred. There was no significant change in the venous partial pressure of the CO₂ level during the procedure. Limitations: The number of patients examined was small. Conclusions: CO₂ insufflation is useful for obtaining clear images of the bile duct during POCS, which makes it possible to determine the qualitative diagnosis and the extent of various bile duct lesions.