Peroral cholangioscopy for diagnosis and therapy of biliary tract disease using an ultra-slim gastroscope

High-resolution video cholangioscopy is expected to improve diagnostic validity for diseases of the biliary tract. We report our experience in using an ultra-slim gastroscope for diagnosis and treatment of biliary tract disease. Cholangioscopy was attempted in 25 cases (22 patients) and succeeded in 22 cases (success rate 88%; 19 patients). Cholangiocellular carcinoma (CCC) was diagnosed by cholangioscopy in five of 10 cases (histopathologically confirmed in four), or ruled out in five. Cholangioscopy was used to detect stones in mega-choledochus (n = 3), to clarify the postoperative condition of the bile ducts (n = 2), to diagnose bile duct varices (n = 1), and to release a dislodged self-expanding metal stent (n = 1), and others. Argon plasma coagulation was successfully completed in a patient with mucin-producing adenomatosis of the bile ducts. One case of non-fatal air embolism occurred before replacing air with CO2 insufflation. In summary, peroral cholangioscopy with an ultra-slim gastroscope is feasible and helpful in selected patients, improving diagnostic validity, and offering new therapeutic interventions. This technique should only be performed using CO2 insufflation.