LAUSR

To determine the best time to perform EPVL treatment by evaluating the efficacy and safety of active stone extraction in treating residual fragments at different time points after RIRS. All participants had renal or upper ureteral stones preoperatively and still had residual stones after receiving RIRS. They were prospectively randomized into four groups: patients in group A received EPVL 3 days after RIRS; patients in group B received EPVL 7 days after RIRS; patients in group C received EPVL 14 days after RIRS; patients in group D did not receive EPVL after RIRS. Follow-up examinations were performed on all participants. The results, including stone size and location, stone-free rate (SFR) and complications, were compared among the groups. There were 176 patients in total. The SFR in groups A, B, C and D were 62.22%, 40.91%, 14.28% and 11.11%, respectively, 7 days after RIRS. At 14 days after RIRS, the SFR was 80%, 59.09%, 42.86% and 26.67% in groups A, B, C and D, respectively. At 28 days after RIRS, the SFR was 91.11%, 84.09%, 76.19% and 51.11% in groups A, B, C and D, respectively. Group A had the highest SFR from 7 to 28 days, and group C had a higher SFR at 28 days after RIRS than group D (P < 0.05). The side effects were less in groups A and B than in group D 28 days after RIRS (P < 0.05). We recommended that the best time to perform EPVL is 3 days after RIRS, because it could achieve a high SFR at any point in time and reduced complications.