Comparison of Ultrasound-assisted and Pure Fluoroscopy-guided Extracorporeal Shockwave Lithotripsy for Renal Stones

Background: In this study, we aimed to compare the efficacy and clinical outcomes of shock wave lithotripsy (SWL) for patients with renal stones using pure fluoroscopy (FS) or ultrasound-assisted (USa) localization with two lithotripters. Methods: We retrospectively identified 425 patients with renal calculi who underwent SWL with either a LiteMed LM-9200 ELMA lithotripter (209 cases), which combined ultrasound and fluoroscopic stone targeting or a Medispec EM-1000 lithotripter machine (216 cases), which used fluoroscopy for stone localization and tracking. The patient demographic data, stone-free rates, stone disintegration rates, retreatment rates and complication rates were analyzed. Results: The USa group had a significantly higher overall stone-free rate (43.6 vs. 28.2%, p<0.001) and stone disintegration rate (85.6 vs. 64.3%, p<0.001), as well as a significantly lower retreatment rate (14.8 vs. 35.6%, p<0.001) and complication rate (1.9 vs. 5.5%, p=0.031) compared with the FS group. This superiority remained significant in the stone size <1cm stratified group. In the stone size >1cm group, the stone-free rate (32.4 vs. 17.8%, p=0.028), disintegration rate (89.2 vs. 54.8%, p=0.031) and retreatment rate (21.6 vs. 53.4%, p<0.001) were still significantly better in the USa group, however there was no significant difference in the complication rate. The most common complication was post-SWL-related flank pain. Conclusion: SWL is a safe and non-invasive way of treating renal stones. this study compared two electromagnetic shock wave machines with different stone tracking systems. LiteMed LM-9200 ELMA lithotripter, which combined ultrasound and fluoroscopic stone targeting outperformed Medispec EM-1000 lithotripter, which used fluoroscopy for stone localization and tracking, with better stone-free rates and disintegration rates, as well as lower retreatment rates and complications with possible reduced radiation exposure.