Results of extracorporeal shock wave lithotripsy for the treatment of upper urinary tract stones.

The treatment results of 697 renal units in 687 patients treated for upper urinary tract stones using a Piezolith 2500 at the Ageo Central General Hospital during the 5-year period between August 1999 and July 2004 were analyzed. The stone-free rate and the success rate were calculated according to the stone size and location. Univariate and multivariate logistic regression analyses were performed to estimate the effect of the patient age, sex, affected side, stone location and stone size on the stone-free rate and the success rate. Overall, the stone-free rate and the success rate at 3 months after treatment were 82.6% and 91.9%, respectively. The stone-free rates in renal and ureteral stones were 60.5% and 88.7%, respectively. The success rates for renal and ureteral stones were 93.6% and 91.6%, respectively. In a univariate logistic regression analysis, patient age and stone size were significant negative factors for both the stone-free rate and the success rate and the stone location in ureter was a significant positive factor only for the stone-free rate. In a multivariate analysis, stone location in the ureter had a positive effect on the stone-free rate, although a negative effect on the success rate. Extracorporeal shock wave lithotripsy for upper urinary tract stones was an effective and safe treatment modality. However, if pre-treatment factors indicate unfavorable outcome, the other treatment options should be considered for the first line therapy.