Extracorporeal shock wave lithotripsy with the Storz Modulith SL20: the first 500 patients.

Our initial experience of extracorporeal shock wave lithotripsy (ESWL) with the Storz Modulith SL20 is reported. A total of 500 patients with 551 renal and 120 ureteric stones, mean diameter 11.9 mm, underwent 746 treatments; 68.2% of patients required a single treatment. The mean treatment rate for renal calculi was 1.4 and for ureteric calculi it was 1.5, rising to 4.2 for staghorns; 62.2% of treatments were performed on an out-patient basis. Analgesia (intravenous fentanyl) was required in 60.9% of treatments for renal calculi but in only 38.2% of those for ureteric calculi. The overall stone-free rate at 3 months was 77.6%, with a further 14.7% of patients having fragments less than 3 mm in diameter that required no further treatment. The stone-free rate was dependent on the site of the stone, with the majority of residual fragments lying in a lower pole calix. There were few complications. The Modulith is an efficient and safe lithotripter capable of treating stones in the kidney and throughout the ureter.