External Comparison of Recent Predictive Nomograms for Stone-Free Rate Using Retrograde Flexible Ureteroscopy with...

Area of Science:

• Urology
• Nephrology
• Surgical Outcomes

Background:

• Flexible ureterorenoscopy (f-URS) is a key procedure for treating kidney stones.
• Predictive scoring systems aid in assessing treatment outcomes.
• The Resorlu-Unsal Stone Score (RUSS) and Modified Seoul National University Renal Stone Complexity (S-ReSC) score are used to evaluate stone complexity.

Purpose of the Study:

• To compare the predictive accuracy of the RUSS and Modified S-ReSC scores for flexible ureterorenoscopy outcomes.
• To identify factors influencing stone-free status after f-URS.

Main Methods:

• Retrospective analysis of 719 patients undergoing f-URS for kidney stones.
• Calculation of RUSS and Modified S-ReSC scores by a single surgeon.
• Logistic regression analysis to determine predictive factors for stone-free status.

Main Results:

• The overall stone-free rate was 70.1%.
• Musculoskeletal deformity, stone size, and RUSS score were independent predictors of stone-free status.
• RUSS demonstrated the highest predictive capability among the evaluated factors (AUC 0.65).

Conclusions:

• Stone size, musculoskeletal abnormalities, and RUSS score significantly impact stone-free status post-f-URS.
• The RUSS score is an independent predictor, but its clinical utility may be limited.
• Development of more comprehensive scoring systems with higher predictive power is warranted for f-URS.