Comparison of electrohydraulic and electromagnetic extracorporeal shock wave lithotriptors for upper urinary tract stones in a single center

PurposeTo compare the efficacy and outcomes of shock wave lithotripsy (SWL) for upper urinary tract stones with an electrohydraulic (EH) and an electromagnetic (EM) lithotriptor in a single center.MethodsThe medical records of 272 patients with upper urinary tract stones2cm in size who underwent SWL with either the Medispec E3000 EH lithotriptor (179 cases) or the Medispec EM1000 EM lithotriptor (93 cases) were reviewed. The demographic data, stone parameters, stone-free rates, and retreatment rates were analyzed.ResultsThe EH group had a higher stone-free rate (53.6 vs. 30.1%, p<0.001) and a lower retreatment rate (32.4 vs. 61.2%, p<0.001) for renal and upper third ureteral stones than the EM group. The stone-free rates for renal stones<1cm (55.5 vs. 32.2%, p=0.045), ureteral stones<1cm (64.5 vs. 42.1%, p=0.028), and renal stones1cm (43.1 vs. 0%, p=0.03) were higher in the EH group. Two patients in the EH group had a renal hematoma needing hospitalization after SWL. There were no complications in the EM group.ConclusionsThe Medispec E3000 EH lithotriptor had higher stone-free rates and lower retreatment rates than the Medispec EM1000 EM lithotriptor for renal stones<2cm and ureteral stones<1cm. Complications were rare.