Investigation of the tissue effects of a new device for intracorporeal lithotripsy--the Swiss Lithoclast.

Currently three modalities are available for intracorporeal stone fragmentation--electrohydraulic, ultrasound and laser lithotripsy. A new device, the Swiss Lithoclast, has been developed by the Departments of Medical Electronics and Urology at the University of Lausanne, Switzerland. This device has been used clinically in several countries for the treatment of stones throughout the human urinary tract. While no adverse outcomes have been reported, the potential tissue effects of the device have not been thoroughly investigated in an animal model. The objective of the present study is to evaluate the possible acute and long-term tissue effects of this instrument on the pig urinary tract. In all acute animals, visible mucosal lesions were seen at the site of probe firing in the bladders and ureters. Histologic examination demonstrated the effects of acute trauma with edema, hemorrhage and mucosal denudation. No significant long-term tissue effects were noted either pathologically or on radiographs in the 3- and 6-week animals. This study confirms our clinical impression that the Swiss Lithoclast effectively fragments urinary calculi and is associated with a large margin of safety.