Acta Scientific Medical Sciences (ASMS)(ISSN: 2582-0931)

Research Article Volume 6 Issue 2

Evaluation of the S.T.O.N.E Score to Predict the Outcomes of Flexible Ureteroscopy for Urinary Stones

Maatougui Jasser*, Raboudi Mehdi, Ben Rejeb Nedhir, Khiari Ramzi and Ghozzi Samir

Department of Urology, Military Hospital of Tunis, University of Tunis El Manar, Tunisia

*Corresponding Author: Maatougui Jasser, Department of Urology, Military Hospital of Tunis, University of Tunis El Manar, Tunisia.

Received: November 22, 2021; Published: January 12, 2022


Over the years, several nomograms have been developed to predict the rate of no fragments after surgery for urinary stones. The objective of this work is to evaluate the S.T.O.N.E score to predict of the effectiveness of flexible ureteroscopy for urolithiasis.

The S.T.O.N.E score evaluates 5 parameters: S (Size): size, T (Topography): location, O (Obstruction): obstruction, N (Number), calculation number, E (Evaluation of Hounsfield Unit) computation density in Hounsfield unit. A score of 1 to 3 points is assigned to each parameter. Between January 2015 and December 2019, 92 interventions were performed. The S.T.O.N.E score was calculated retrospectively for each patient and correlated with the absence of residual fragment 3 months after flexible ureteroscopy (SFR: Stone Free Rate). We tried to determine the threshold value of this score through the analysis of the receiver operator curve.

The average S.T.O.N.E Score was 9.94. The Stone free rate was 81%. After statistical analysis, the area below the ROC curve was 0.73 IC-95% [0.624; 0.836]. In our study, a threshold of 10 or less was associated with an SFR of 59.3%. In comparison, a preoperative S.T.O.N.E Score strictly greater than 10 was associated with a significantly low stone free rate of 39.3%, p = 0.003.

In light of our results, the S.T.O.N.E score seems to be an easy, reliable and reproducible tool to predict the outcome of a flexible ureteroscopy.

Keywords: Nomograms; Flexible Ureteroscopy; Urinary Stones


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Citation: Maatougui Jasser., et al. “Evaluation of the S.T.O.N.E Score to Predict the Outcomes of Flexible Ureteroscopy for Urinary Stones”.Acta Scientific Medical Sciences 6.2 (2022): 61-64.


Copyright: © 2022 Maatougui Jasser., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


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