Comparable clinical outcomes with two lithotripters having substantially different acoustic characteristics

Abstract

A consecutive case study was conducted to assess the clinical performance of the Lithogold, an electrohydraulic lithotripter having a relatively low P + and broad focal width (FW) (~20 MPa, ~20 mm), and the electromagnetic Storz-SLX having higher P + and narrower FW (~50 MPa, 3–4 mm). Treatment was at 60 SW/min with follow-up at ~2 weeks. Stone free rate (SFR) was defined as no residual fragments remaining after single session SWL. SFR was similar for the two lithotripters (Lithogold 29/76 = 38.2%; SLX 69/142 = 48.6% p = 0.15), with no difference in outcome for renal stones (Lithogold 20/45 = 44.4%; SLX 33/66 = 50%, p = 0.70) or stones in the ureter (Lithogold 9/31 = 29%; SLX 36/76 = 47.4%, p = 0.08). Stone size did not differ between the two lithotripters for patients who were not stone free (9.1±3.7 mm for Lithogold vs. 8.5±3.5 mm for SLX, P = 0.42), but the stone-free patients in the Lithogold group had larger stones on average than the stone-free patients treated with the SLX (7.6±2.5 mm vs. 6.2±3.2 mm, P = 0.005). The percentage of stones that did not break was similar (Lithogold 10/76 = 13.2%; SLX 23/142 = 16.2%). These data present a realistic picture of clinical outcomes using modern lithotripters, and although the acoustic characteristics of the Lithogold and SLX differ considerably, outcomes were similar. [NIH-DK43881.]