Balancing the ratio - to the find the appropriate combination of flexible renoscope and different access sheath and determine their effects on post operative outcomes

Background: To evaluate the efficacy of the ratio of FURS and ureteral access sheath diameter, aiming to identify the most appropriate combination for improved post-operative outcomes Method: Prospective, cross - sectional study conducted at Tabba kidney Institute. 300 patients were enrolled from August 2025 till October 2025. Patients were randomly classified in three groups on basis of ureteral access sheath sizes and endoscope to sheath ratio. Group A (ureteral access sheath 9/11) and group B (ureteral access sheath 10/12) group 3 (sheath 11/13) with FURS size of 8.6 Fr. Peri-operative demographics detail, pre-operative stone size, location, intra-operative and post-operative complications, fluoroscopy time and stone free rates on follow up were compared. SPSS-23 was used to analyze data. Results: There were 70.40 % males in Group A, 60.40% in group B and 65.30% in group C and 29.60%, 39.60% and 34.70% females in groups A, B and C respectively. There was highest operative time in Group A (70.3 ± 20.9 min) p value of 0.023 with equivocal stone sizes in all groups. Conclusion: The combination of 11/13Fr ureteral access sheath with an 8Fr flexible URS offers ideal balance for optimal stone clearance by providing remarkable visibility and maintaining adequate intra-pelvic pressure. This approach effectively reduces the risk of postoperative complications and minimizes the risk of ureteric injury promoting safe surgical outcomes.