Treatment of 2019 cases with upper urinary tract calculi using a piezoelectric lithotriptor ESL-500A

PURPOSE: We evaluated the results of extracorporeal shock wave lithotripsy (ESWL) in a large number of cases with upper urinary tract calculi, and reported the strategy how to improve the efficacy and safety of ESWL. PATIENTS AND METHOD: Eight hundred fifteen patients with renal calculi and 1,204 patients with ureteral calculi were treated using a piezoelectric ultrasound-guided lithotriptor, Toshiba ESL-500A. Auxiliary measures were needed in 51 cases (2.5%) and 1,968 cases (97.5%) were treated by in situ procedures. ESWL was performed with the optimal positioning of the patient and under the continuous monitoring by ultrasound system. The visibility of stones was improved by removal of abdominal gas and administration of diuretic agent to dilate the ureter. Cases with urinary tract infection were medicated by antibiotics and the obstruction of the urinary tract was cleared away as soon as possible. RESULTS: Including the cases with residual fragments less than 4 mm, the success rates at one month after the treatment were 97.7% and 98.7% for the renal and ureteral calculi, respectively. The mean numbers of sessions were 1.49 for renal calculi and 1.16 for ureteral calculi. Multiple sessions were required in 24.2% of renal calculi and 12.0% of ureteral calculi. No serious complication has been observed except for three cases, which were sepsis after ESWL, anuria in a solitary kidney, and pyonephrosis caused by Steinstrasse with urinary infection, respectively. CONCLUSION: ESWL using ESL-500A is an efficient treatment of upper urinary tract calculi which has higher pulverization rate and fewer complications in the adequate procedure.