[Clinical experience of the newly developed electrohydraulic lithotripter].

The electrohydraulic lithotripter (EHL) is a calculus-breaking device used in percutaneous nephrolithotomy (PNL). The conventional EHL has a shortcoming in that its breakability decreases in the saline irrigation environment. The newly developed EHL (Lithotron EL-21 OLYMPUS) is designed to discharge optimum sparks during saline irrigation, without having to dilute the solution, thus providing greater convenience. We used the new EHL in 17 cases of renal calculi, 11 cases of ureteral calculi and 2 cases of reno-ureteral calculi, with a breakup efficiency of 96.7%. As a direct, incidental complication, perforation of the ureter occurred in one case of ureteral calculi (uneventful spontaneous recovery detected 3 days afterward). The new EHL has a breakup capability suitable for the PNL: the EHL provides a safe procedure, provided that one takes sufficient caution to the correct positioning of the probe against the target calculus when activating it. Since the probe shaft is flexible, permitting use with the flexible endoscope, the EHL is particularly effective in treating ureteral and renal calculi in cases where access by the rigid US probe is not feasible. One disadvantage of the EHL is that it lacks the fragment-collecting capability that the ultrasound lithotripter features.