Dilation assisted stone extraction for complex biliary lithiasis: Technical aspects and practical principles

Common bile duct stones are frequently diagnosed worldwide and are one of the main indications for endoscopic retrograde cholangio-pancreatography. Endoscopic sphincterotomy (EST) has been used for the removal of bile duct stones for the past 40 years, providing a wide opening to allow extraction. Up to 15% of patients present with complicated choledocholithiasis. In this context, additional therapeutic approaches have been proposed such as endoscopic mechanical lithotripsy, intraductal or extracorporeal lithotripsy, or endoscopic papillary large balloon dilation (EPLBD). EPLBD combined with EST was introduced in 2003 to facilitate the passage of large or multiple bile duct stones using a balloon greater than 12 mm in diameter. EPLBD without EST was introduced as a simplified technique in 2009. Dilation-assisted stone extraction (DASE) is the combination of two techniques: EPLBD and sub-maximal EST. Several studies have reported this technique as safe and effective in patients with large bile duct stones, without any increased risk of adverse events such as pancreatitis, bleeding, or perforation. Nevertheless, it is difficult to analyze the outcomes of DASE because there are no standard techniques and definitions between studies. The purpose of this paper is to provide technical guidance and specific information about the main issues regarding DASE, based on current literature and daily clinical experience in biliary referral centers.