Treatment of Moderate Sized Renal Pelvis Calculi: Stone Clearance Time Comparison of Extracorporeal Shock Wave Lithotripsy and Retrograde Intrarenal Surgery.

PURPOSE To compare the stone clearance times in patients undergoing extracorporeal shock wave lithotripsy (SWL) or retrograde intrarenal surgery (RIRS) for single radiopaque renal pelvis stones 10-20 mm in size. The results of this study may guide urologists and patients and aid in selecting the optimal preoperative treatment. MATERIALS AND METHODS Between January 2013 and February 2015, we conducted a retrospective study and collected data from 333 patients treated with SWL (n = 172) or RIRS (n = 161). We included successfully treated patients with a single radiopaque renal pelvis stone 10-20 mm in size to calculate stone clearance times. RESULTS The average stone size for the SWL group was 14.62 ± 2.58 mm and 14.91 ± 2.92 mm for the RIRS group. The mean Hounsfield unit (HU) of the patients was 585.40 ± 158.39 HU in the SWL group and 567.74 ± 186.85 HU in the RIRS group. Following full fragmentation, the mean stone clearance time was 26.55 ± 9.71 days in the SWL group and 11.59 ± 7.01 days in the RIRS group (P < .001). CONCLUSION One of the most overlooked parameters in urinary stone treatments is stone clearance. We believe this study will shed light for those who aim to conduct larger randomized prospective studies.&nbsp.