Success Rate of Extracorporeal Shock Wave Lithotripsy according to Operator

Kim, Byung Hoon; Chung, Young Churl; Chang, Hyuk Soo; Park, Choal Hee

Abstract

PURPOSE: The purpose of this study was to measure and compare the operator specific success rate of extracorporeal shock wave lithotripsy (ESWL), performed by 12 urologists in 1 unit, to determine the interoperator variation.
MATERIALS AND METHODS
Between September 1995 and September 2002, 1,434 patients with renal or ureteral stones received 2,697 ESWL treatments by 12 urologists (surgeons A to L), using a Storz Modulith SLX lithotripter. Measures of the patient outcomes included demographics, stone characteristics, technical details of lithotripsy, and session stone-free and final success rates according to operating urologist.
RESULTS
The mean session stone-free and final success rates were 44.8 (22.1-65.3) and 94.5% (86.7-99.4), respectively. Significant differences existed in mean number of shocks, fluoroscopy time and maximum treatment voltage delivered among the surgeons (p<0.05). Surgeon H had significantly higher session stone-free (65.3%, p<0.05) and final success rates (99.4%, p>0.05). The mean number of shocks was higher for surgeons J (3,683) and H (3,606) than for the others (p<0.05). The mean fluoroscopy time was higher for surgeon H, 4.44 minutes, than for the others (p<0.05). Mean maximum treatment voltage was higher for surgeons H (8.27), J (8.10) and I (8.05) than for the others (p<0.05). Multiple analyses were performed by surgeon H. The fluoroscopy time (p=0.001) and the maximum treatment voltage (p=0.012) contributed greatly to the best results.
CONCLUSIONS
We demonstrated clinically and statistically significant intra-institutional differences in the final success rate following ESWL. The best results were obtained by the urologist who used the longest fluoroscopy time and highest maximum treatment voltage.