Clinical Utility and Safety of a Novel Ultraslim Catheter‐Type Peroral Cholangioscope/Pancreatoscope: A Single‐Center Case Series

Peroral cholangioscopy (POCS) and peroral pancreatoscopy (POPS) enable direct intraductal visualization for pancreatobiliary disease diagnosis and management. Nonetheless, conventional devices have relatively large diameters, limiting their use in narrow ducts. This single‐center, retrospective, observational study aimed to evaluate the feasibility and safety of a novel ultraslim catheter‐type POCS/POPS (UCPOCS/UCPOPS) (distal outer diameter: 2.3 mm) in 12 patients who underwent UCPOCS or UCPOPS from November 2022 to August 2024. UCPOCS was performed in eight patients with bile duct stones ( n = 3), biliary strictures ( n = 2), intrahepatic cholangiocarcinoma ( n = 1), post‐hepatectomy biliary bleeding ( n = 1), and acute cholecystitis requiring endoscopic naso‐gallbladder drainage ( n = 1). UCPOPS was performed in four patients for postoperative pancreatic duct evaluation ( n = 2) and intraductal papillary mucinous neoplasm assessment ( n = 2). Technical success, defined as successful scope insertion into the target duct, was achieved in all cases. Clinical success was achieved in 11/12 cases (91.7%), including diagnostic clinical success in 10/11 diagnostic cases (90.9%) and procedural utility success in 1/1 procedural utility case (100%). The smallest successfully visualized duct measured 1.8 mm in diameter based on fluoroscopic estimation at the intended insertion site. One patient developed mild post‐endoscopic retrograde cholangiopancreatography pancreatitis, which resolved with conservative management; no other adverse events were observed. The median total procedure time and scope insertion time were 42 and 7 min, respectively. These findings indicate that the UCPOCS or UCPOPS is a feasible and safe intraductal visualization tool for pancreatobiliary diseases, particularly in patients with narrow ducts or challenging anatomy. Trial Registration : N/A.