The Role of Artificial Intelligence Combined With Digital Cholangioscopy for Indeterminant and Malignant Biliary Strictures: A Systematic Review and Meta-analysis.

Diagnosis is unchanged and still follows the separate ESGE diagnostic guideline (Endoscopy 2025;57:166-185). Start with MRI/MRCP plus laboratory tests, read CA19-9 only after decompression, and check IgG4 when IgG4-related sclerosing cholangitis is suspected. For distal extrahepatic strictures with no pancreatic mass, do combined same-session EUS-guided tissue acquisition plus ERCP brushing and biopsy. For perihilar strictures, sample by ERCP first and move to cholangioscopy-guided biopsy if the result is indeterminate. Do not place an uncovered SEMS (USEMS) until malignancy is confirmed. Management now follows the 2026 ESGE biliary stricture management guideline, which replaces the 2018 stenting guideline and brings it into line with the 2022 therapeutic EUS guideline. Benign: post-cholecystectomy strictures get temporary multiple plastic stents (MPSs), exchanged every 3-4 months with as many stents as possible, for about 12 months. A fully covered SEMS (FCSEMS) is an option only if the stricture is more than 2 cm below the hepatic confluence or the patient will not comply with repeated ERCPs. Anastomotic strictures after liver transplant get MPSs, or a temporary FCSEMS if more than 2 cm below the confluence. Nonanastomotic post-transplant strictures that can be treated endoscopically get MPSs plus balloon dilation if needed. Chronic pancreatitis strictures get a temporary 8-10 mm FCSEMS for 6-12 months. High-grade PSC strictures get balloon dilation alone, with no stent, because stenting adds no benefit and may add adverse events. Endotherapy is indicated for a benign stricture with liver tests raised for more than 1 month and/or cholangitis. Malignant distal: drain before surgery only selectively (cholangitis, severe jaundice or pruritus, delayed surgery). When drainage is needed before surgery or neoadjuvant therapy, or for palliation, place a 10-mm SEMS endoscopically. Endoscopic drainage is preferred over surgery or PTBD for inoperable obstruction. Malignant hilar: manage in high-volume centres with a hepatobiliary multidisciplinary team (MDT). ERCP is preferred over PTBD for preoperative drainage. Palliate Bismuth I-II with ERCP. For Bismuth III-IV, ERCP or ERCP combined with EUS-guided drainage (EUS-BD) is preferred over primary PTBD, with PTBD as a complement if needed. For proven Bismuth II-IV, aim to drain more than 50%, ideally 70% or more, of the viable nonatrophic liver volume using several routes as needed. Use plastic stents when the drainage strategy is undefined or the centre is not expert. USEMS are for expert centres when the diagnosis is proven, the tumour is unresectable, and complete drainage is predicted. After failed or unfeasible ERCP, EUS-BD is recommended over PTBD. Use hepaticogastrostomy (EUS-HGS) if there is a duodenal stricture, and EUS-HGS or choledochoduodenostomy (EUS-CDS) if there is not. PTBD is used if EUS-BD fails. In surgically altered anatomy, benign disease gets enteroscopy-assisted ERCP first; malignant disease gets enteroscopy-assisted ERCP or EUS-BD. Give antibiotics before ERCP in selected cases: predicted incomplete drainage, hilar strictures, immunocompromised patients, PSC, cholangioscopy. This follows the ESGE ERCP-adverse-events guideline. Etiology-specific care (Strasberg injuries, IgG4-SC, Mirizzi, choledochal cysts) is unchanged.