Factors Predicting the Success of Extracorporeal Shock Wave Lithotripsy in the Treatment of Ureteric Calculi
Objective: To evaluate the success of extracorporeal shock wave lithotripsy (ESWL) in the treatment of ureteric calculi and determine the factors which influence outcome. Patients and methods: A retrospective audit of patients with a single ureteric stone receiving ESWL was performed. Success was defined as complete stone clearance on post-treatment imaging. Patient demographics and stone characteristics were correlated to ESWL outcome. Results: 108 patients met the inclusion criteria for this study. The mean age of the patients was 52.5 years (range 24–89 years). 80% (86/108) of patients were male. Stone sizes varied from 4 to 19 mm (mean 7.92 mm). The overall ESWL success rate for ureteric stones was 79%. Treatment was more effective for smaller ( p = 0.003) and more located stones ( p = 0.035). Stone size correlated with number of treatments required ( p =0.005). A JJ stent in situ at the time of ESWL reduced the success rate ( p = 0.002). Conclusions: Stone size, site in the ureter, and the presence of a JJ stent were predictors of ESWL success. Our study from a District General Hospital in the UK demonstrates that ESWL may be used with high efficacy to treat ureteric stones.