Electrohydraulic lithotripsy (EHL) for the treatment of large retained common duct stones

Retained biliary stones may be too large for extraction through the existing T-tube tract. It may be necessary to dilate the tract, crush the stones or use endoscopic papillotomy. There are reports of stones and the extracting basket becoming stuck in the T-tube tract and tract ruptures caused by extracting large stones. In this study electrohydraulic lithotripsy (EHL) is used in combination with T-tube tract choledochoscopy for the fragmentation of large stones prior to basket extraction. T-tube choledochoscopy was performed under IV sedation and sterile conditions no sooner than one month following common bile duct exploration. The Olympus 4.9-mm choledochoscope was passed through the T-tube tract to visualize the stone. A #5 Fr EHL probe was passed through the endoscope and advanced to within 1 mm of the surface of the stone. EHL discharge was started at a low energy level being increased until the spark discharges caused stone fragmentation. The resultant stone fragments were basket extracted under direct vision. The procedure was used in twelve patients with removal of all stones in eleven patients. Eight patients were treated with one endoscopic session. Because of multiple stones, two patients required two sessions and one patient four sessions. In one patient stone position prevented adequate fragmentation and endoscopic papillotomy also failed. Repeat choledochoscopy and EHL were successful. There were no complications of EHL or choledochoscopy in any of the patients. EHL was both effective and safe for fragmentation of large common duct stones when performed under direct vision using a choledochoscope.