Comparison of Electrohydraulic and Electromagnetic Shock Wave Lithotripsy for Upper Urinary Tract Stones in Elderly Patients

Backgrounds In this study we compared the clinical outcomes of elderly patients with upper urinary tract stones who underwent extracorporeal shock wave lithotripsy (ESWL) with two different machines, an electrohydraulic (EH) and an electromagnetic (EM) lithotripter. Methods A retrospective review of medical records was performed of 238 patients (EH 168, EM 70) aged 65 years or older with upper urinary tract stones who underwent ESWL at two branches of the same institution between 2007 and 2015. The demographic data, stone parameters, stone-free rate, retreatment rate, and complication rate in both groups were analyzed. Results There was no significant difference between the EH and EM groups in terms of stone free rate (43.5% vs. 34.3%, p > 0.05) regardless of stone site or size. EM group had a higher retreatment rate than EH group (31.5% vs. 50.0%, p = 0.007). Complication rates were similar (22.0% vs. 27.1%, p > 0.05). The most common complication was flank pain. Two EH group patients had subcapsular renal hematomas. Conclusions Our study showed that elderly patients with upper urinary tract stones undergoing ESWL with EH and EM machines had comparable stone free rates and complication rates, but a higher retreatment rate was seen with EM machines.