Biliary lithotripsy as an adjunct to laparoscopic common bile duct stone extraction

We investigated various energy sources and delivery systems suitable for fragmentation of common duct calculi by a laparoscopic technique. We evaluated electrohydraulic lithotripsy (EHL) using 1.9-Fr probe delivering 80 W and laser lithotripsy using a 200-micron(s) fiber delivering 30-70 mJ/pulse at 5-20 Hz. In vitro biliary stone fragmentation analysis suggested that the laser lithotripsy produced a more controllable fragmentation than EHL. Initial attempts to employ EHL techniques in animal models resulted in common bile duct injury or inadequate fragmentation of stones. In contrast, biliary lithotripsy was accomplished in pigs using the pulsed-dye laser at 10 Hz and 60 mJ/pulse. Histologic evaluation revealed no evidence of ductal injury related to laser stone fragmentation. Subsequently, laser common duct lithotripsy was used in two human subjects. One patient had a 1.8-cm impacted ampullary stone and one patient had a 3-cm intrahepatic stone. In both cases, the stones were removed laparoscopically after laser fragmentation. Our experience suggests that the laser lithotripsy may facilitate laparoscopic common duct stone extraction procedures.