Factors Predicting the Outcome of Retrograde Flexible Ureterorenoscopy for the treatment of Renal Stones

Background: Flexible ureterorenoscopy (FURS) is widely used in surgical treatment of renal stones, due to the tendency toward minimally invasive options. This study conducted to evaluate factors affecting outcomes of FURS. Patients and methods: A retrospective analysis of patients with renal stones who underwent FURS at Al-Azhar University Hospitals (Al-Hussein and Sayed Galal), Cairo, Egypt. This analysis involved patients who underwent FURS in period between October 2020 to June 2022, only patients with complete data were involved in this study. Results: Out of 187 patients underwent FURS for renal stone in the aforementioned period, 152 had complete data. The mean age of patients was 43.7±12.5 years. 58 (38.2%) were females while 94 (61.8%) were males. The mean stone burden was 16.2±5.7 mm. The overall stone free rate (SFR) was126/152 patients after 3 sessions of FURS (82.4%), while the SFR after one and two session was 104 patients (68%) and 124 patients (81%) respectively. Univariate analysis of factors that may affect the stone free status (SFS) demonstrate that stone burden, stone location, stone number and renal malformations were found to have a significant effect on SFS, while in multivariate analysis stone location was the only predictive factor of SFS. Conclusion: FURS proved of high efficacy and limited major complications in treatment of renal stones. Multivariate analysis revealed that stone location had a strong predictive value on the SFS, while stone burden had a strong predictive value on the incidence of intra and post operative complications.