An 84-year-old woman underwent endoscopic papillary large balloon dilatation (EPLBD), electronic hydraulic lithotripsy (EHL) and temporary insertion of one plastic stent (PS) for large and heaped common bile duct stones at her previous hospital, but it was difficult to remove these stones. Although she underwent extracorporeal shock wave lithotripsy (ESWL) in our hospital, these stones didn't be fractured. After insertion of two PSs and exchange of them every six months, the amount and size of stones decreased gradually. As a result, we succeeded in removing stone after one and a half years. It was suggested that an increase of the friction effect between the stones and the PSs due to insertion of two PSs resulted in decrease of the amount and size of stones.
