Accessing the Pancreatobiliary System via Lumen-Apposing Metal Stents: A State-of-the-Art Review of Endoscopic Ultrasound-Directed Interventions

The growing number of bariatric and oncologic gastrointestinal and hepatopancreatobiliary surgeries has fueled the increased need for biliary interventions in patients with surgically altered anatomy (SAA), where standard endoscopic retrograde cholangiopancreatography (ERCP) is often unfeasible. Traditional alternative methods, such as enteroscopy- or laparoscopy-assisted ERCP, are associated with technical and logistical limitations. Endoscopic ultrasound (EUS)-directed ERCP uses lumen-apposing metal stents (LAMS) to create temporary anastomoses between adjacent lumens, thus restoring access for standard ERCP. These procedures include EUS-directed transgastric (EDGE), transenteric (EDEE), transduodenal (EDDE), and transcholedochal/transcystic (EDCE) ERCP. This review provides an evidence-based analysis of the available techniques and comparative outcomes, with a particular focus on technical and strategic aspects including: (1) how to create an EUS-guided anastomosis across different surgical scenarios; (2) how to perform a through-the-LAMS ERCP, including endoscope and accessory selection, ERCP timing and LAMS fixation; and (3) how to manage the fistula after completion of therapy, including timing of LAMS removal and fistula closure. An algorithm is proposed to guide the endoscopist through the complex decision-making inherent to pancreatobiliary interventions in SAA.