[Stone free rate assesment after percutaneous nephrolithotomy using nephrolitometric nomogram].

Area of Science:

• Urology
• Nephrology
• Surgical Prognostics

Background:

• Percutaneous nephrolithotomy (PCNL) is the standard for kidney stones >2cm.
• Accurate prognosis for complete stone resolution is crucial but current tools are limited.

Purpose of the Study:

• Evaluate the stone-free rate (SFR) using the Clinical Research Office of the Endourological Society (CROES) nomogram for PCNL.
• Suggest modifications to the CROES nomogram to improve patient stratification.

Main Methods:

• Retrospective analysis of 126 patients undergoing PCNL.
• Application of the CROES nephrolithometric nomogram.
• Modification of the nomogram into three groups (80-110, 111-170, >170 points) to assess SFR.

Main Results:

• The original nomogram showed limited discrimination for intermediate scores.
• Modified groups I, II, and III achieved SFRs of 12.5%, 50%, and 80%, respectively (p=0.000).
• The modified scale improved differentiation between low, intermediate, and high SFR groups.

Conclusions:

• The CROES nomogram accurately predicts SFR for simple and complex kidney stones.
• The proposed modification enhances the nomogram's ability to differentiate intermediate-risk patients.
• Improved prognostic tools are essential for optimizing PCNL outcomes.