Experience in 3,500 patients with urinary stones treated with the Dornier HM-4 bath-free lithotriptor

During a 3-year period, hundreds of patients underwent ESWL treatment with the Dornier HM-3 and HM-4 lithotriptors operating at our institution. Our experience in 3,500 patients treated with the HM-4 bath-free lithotriptor is reported. Patients with radiolucent or cystine stones, stones larger than 3 cm or staghorn calculi, multiple stones with a total burden of more than 3 cm and those not amenable to follow-up were excluded from the study. The overall stone-free rate was 70.7% and 81% at 1 and 3 months, respectively. The stone-free rates at 1 and 3 months were further determined by the exact location of each stone within the urinary tract. Stone-free rates at 3 months ranged from 90.84% for renal pelvic stones to 71.08% for lower calyceal stones, while the stone-free rates for ureteral calculi ranged from 80.85% for upper third unstented ureteral stones to 92.92% for lower ureteral stones. The overall complication rate was 6.02% with a 1.2% post-ESWL intervention rate (ureteroscopy or placement of percutaneous nephrostomy or stent).