Predictors of success for stone fragmentation and stone-free rate after extracorporeal shockwave lithotripsy in the treatment of upper urinary tract stones.

PURPOSETo evaluate factors affecting the success rate of stone fragmentation and stone-free rate after extracorporeal shockwave lithotripsy (SWL) in treatment of upper urinary tract stones.MATERIALS AND METHODSA total of 121 patients with upper urinary tract calculi underwent SWL treatment.RESULTSSuccess rate of stone fragmentation after SWL was 73.6% (89/121). In 89 patients who had success of breaking stones, 71 patients were followed up for the assessment of stone-free status, of whom 51 (71.8%) patients were stone-free at 3-month follow-up. Among four prognostic factors, including body mass index (BMI), stone size, stone position, and hydronephrosis, BMI and stone position had a significant impact on the success rate of stone fragmentation (P = .04 and U1: P = .0108, respectively). Among five prognostic factors of BMI, stone size, stone position, hydronephrosis, and times of SWL treatments, stone size was the only factor with significant impact on the stone-free rate (middle: P = .0229).CONCLUSIONOur study suggests that stone fragmentation and stone-free rate after SWL treatment for upper urinary tract stones can be predicted.