The Outcomes of Pre-Stenting on Renal and Ureteral Stones: A Meta-Analysis

BACKGROUND: Pre-stenting (PS) on the outcomes of semirigid and flexible ureteroscopic lithotripsy for a different upper urinary urolithiasis remains controversial. We performed a meta-analysis comparing the outcomes of ureteroscopic lithotripsy between PS and non-PS. MATERIALS AND METHODS: Randomized, controlled trials and observational studies comparing PS and non-PS were identified from electronic databases. Stone-free rate (SFR), operative time, and complications were compared by qualitative and quantitative syntheses (meta-analyses). RESULTS: Eleven articles were included in this study. Nearly, all of recently published studies exhibited relatively moderate or high quality during quality assessment. PS was more likely to achieve good SFR compared with non-PS (p < 0.00001). The subgroup results indicated that PS improved the SFR for renal stones and the stones dealt by flexible ureteroscopy (p = 0.0002; p < 0.0001, respectively; some ureteral stones were dealt by flexible ureteroscopy). Ureteral stones and the stones dealt by semirigid ureteroscopy were not influenced by PS (p = 0.62; p = 0.90, respectively). PS is equal as non-PS in terms of operative time for renal stones and the renal and ureteral stones dealt by flexible ureteroscopy (p = 0.47; p = 0.05). No significant difference was found in major complications between the 2 groups for total or for the subgroup of renal stones (p = 0.3; p = 0.69). CONCLUSIONS: For ureteral stones or the stones dealt by semirigid ureteroscopy, PS does not show any benefits. For renal stones or the stones dealt by flexible ureteroscopy, PS improves the SFR and may be as safe as non-PS.