EXTRACORPOREAL SHOCK-WAVE LITHOTRIPSY FOR BLADDER STONES

Between December 1989 and July 1991, 29 patients with bladder stones w ere treated on the MPL 9000 extracorporeal shock wave lithotriptor usi ng ultrasound for localisation. The mean stone dimensions were 22.65 x 15.17 mm (< 400 mm2 in 20 patients); 75% of patients required only 1 ESWL session but the largest stone (2025 mm2) required 3. Whilst large r stones tended to require more shock waves, linear regression analysi s showed a poor fit and factors other than size (operator experience a nd stone hardness) may determine the number of shock waves required. S atisfactory fragmentation was obtained in all patients. All were treat ed under intravenous analgesia without anaesthesia. Three patients als o had outflow obstruction and were treated by transurethral resection of the prostate (TURP) on the day after completing ESWL. ESWL prior to TURP reduces the morbidity and operating time associated with endosco pic therapy of bladder stones. Macroscopic fragments remaining after E SWL can be washed out at TURP.