Recent advances in endoscopic management of difficult bile duct stones.

Endoscopic treatment is now recognized worldwide as the first-line treatment for bile duct stones. Endoscopic sphincterotomy combined with basket and/or balloon catheter is generally carried out for stone extraction. However, some stones are refractory to treatment under certain circumstances, necessitating additional/other therapeutic modalities. Large bile duct stones are typically treated by mechanical lithotripsy. However, if this fails, laser or electrohydraulic lithotripsy (EHL) is carried out under the guidance of conventional mother-baby cholangioscopy. More recently, direct cholangioscopy using an ultrathin gastroscope and the newly developed single-use cholangioscope system - the SpyGlass direct visualization system - are also used. In addition, extracorporeal shock wave lithotripsy has also been used for stone fragmentation. Such fragmentation techniques are effective in cases with impacted stones, including Mirizzi syndrome. Most recently, endoscopic papillary large balloon dilationhas been introduced as an easy and effective technique for treating large and multiple stones. In cases of altered anatomy, it is often difficult to reach the papilla; in such cases, a percutaneous transhepatic approach, such as EHL or laser lithotripsy under percutaneous transhepatic cholangioscopy, can be a treatment option. Moreover, enteroscopy has recently been used to reach the papilla. Furthermore, an endoscopic ultrasound-guided procedure has been attempted most recently. In elderly patients and those with very poor general condition, biliary stenting only is sometimes carried out with or without giving subsequent dissolution agents.