[Extracorporeal lithotripsy using the Lithoring multi-one, a third generation lithotripter].

The Lithoring multi-one is a lithotripter recently developed in Italy. Its main features are: (1) spark gap generator with large ellipsoid with tunable power for treatments with or without analgesia (2) localization by fluoroscopy and ultrasounds without moving the patient (3) isocentric variation of shock wave window (4) multi-functional table. It can treat both urinary and biliary stones. Herein we described (1) the experimental in vitro studies, including those carried out by intentionally changing the direction of the blast path during the treatment (2) the experimental in vivo studies on pigs which demonstrated a rate of side effects favourably comparable with that of other spark gap lithotripters (3) the clinical experience on urinary stones which started in May, 1989. The first 50 patients were treated without anaesthesia with an average of 1700 shock waves at 19.2 Kv. 37 patients had stones larger than 1 cm. 13 patients had ureteral stones. Two patients had complete staghorn stones. The disintegration rate was 97.9 percent, the overall stone-free rate at 3 months follow-up was 83.3 percent and the retreatment rate was 1.29 treatments for patients. No complication occurred.