A Prospective Randomised Trial Comparing the Modified HM3 with the MODULITH® SLX-F2 Lithotripter

Abstract

BackgroundThe relative efficacy of first- versus last-generation lithotripters is unknown. ObjectivesTo compare the clinical effectiveness and complications of the modified Dornier HM3 lithotripter (Dornier MedTech, Wessling, Germany) to the MODULITH® SLX-F2 lithotripter (Storz Medical AG, Tägerwilen, Switzerland) for extracorporeal shock wave lithotripsy (ESWL). Design, setting and participantsWe conducted a prospective, randomised, single-institution trial that included elective and emergency patients. InterventionsShock wave treatments were performed under anaesthesia. MeasurementsStone disintegration, residual fragments, collecting system dilatation, colic pain, and possible kidney haematoma were evaluated 1 d and 3 mo after ESWL. Complications, ESWL retreatments, and adjuvant procedures were documented. Results and limitationsPatients treated with the HM3 lithotripter (n=405) required fewer shock waves and shorter fluoroscopy times than patients treated with the MODULITH® SLX-F2 lithotripter (n=415). For solitary kidney stones, the HM3 lithotripter produced a slightly higher stone-free rate (p=0.06) on day 1; stone-free rates were not significantly different at 3 mo (HM3: 74% vs MODULITH® SLX-F2: 67%; p=0.36). For solitary ureteral stones, the stone-free rate was higher at 3 mo with the HM3 lithotripter (HM3: 90% vs MODULITH® SLX-F2: 81%; p=0.05). For solitary lower calyx stones, stone-free rates were equal at 3 mo (63%). In patients with multiple stones, the HM3 lithotripter’s stone-free rate was higher at 3 mo (HM3: 64% vs MODULITH® SLX-F2: 44%; p=0.003). Overall, HM3 lithotripter led to fewer secondary treatments (HM3: 11% vs MODULITH® SLX-F2: 19%; p=0.001) and fewer kidney haematomas (HM3: 1% vs. MODULITH® SLX-F2: 3%; p=0.02). ConclusionsThe modified HM3 lithotripter required fewer shock waves and shorter fluoroscopy times, showed higher stone-free rates for solitary ureteral stones and multiple stones, and led to fewer kidney haematomas and fewer secondary treatments than the MODULITH® SLX-F2 lithotripter. In patients with a solitary kidney and solitary lower calyx stones, results were comparable for both lithotripters.