Endoscopic Ultrasound-guided Biliary Interventions

Endosonographic/endoscopic ultrasound–guided biliary drainage/anastomosis (EUS-BD/A) is widely accepted as a salvage procedure when conventional endoscopic retrograde cholangiopancreatography (ERCP) fails or is difficult. Although this procedure carries risks of severe adverse events (AEs), including perforation and bile leakage due to unattached organs, the risk of postprocedural pancreatitis in EUS-BD/A is extremely low. The intrahepatic bile duct approach is more challenging than extrahepatic because it involves penetrating the liver parenchyma. To establish EUS-BD/A as a standard primary biliary drainage procedure, it is essential to confirm its feasibility compared with ERCP, evaluate expanded indications, develop dedicated devices, and establish AE management strategies. EUS-BD/A showed similar technical and clinical success rates and AE rates, with ERCP and incidence of pancreatitis was significantly lower. Expanded indications for EUS-BD/A include primary drainage, preoperative use, pediatric patients, patients with massive ascites, and reintervention for stent occlusion; however, further evidence is required to support these indications. The development of devices to improve technical success and reduce AE rates is critical to establishing this procedure, but current devices remain insufficient for EUS-BD/A. In Japan, dedicated devices for EUS-BD/A include sharp-tip bougie dilators, drill-type dilators, sharp-tip balloon dilators, and covered self-expandable metallic stents with effective anchoring. Reducing the gap between the device and guidewire is particularly important for endosonographic/endoscopic ultrasound–guided hepaticogastrostomy. Management of AEs and the establishment of follow-up strategies are crucial as well. We herein summarize the prevention and management of AEs, including mediastinitis due to esophageal puncture, bile leakage, bleeding, and perforation, and introduce our follow-up strategy. Our ultimate goal is to establish EUS-BD/A as a standard primary biliary drainage procedure. Continuous efforts are necessary to advance various aspects of EUS-BD/A.