改良S.T.O.N.E.肾结石评分系统预测软性输尿管镜碎石术术后结石清除率的准确性研究

Accuracy of modified S.T.O.N.E. nephrolithometry scoring system in predicting stone-free rate after flexible ureteroscopic lithotripsy

摘要:

目的： 对已建立的改良S.T.O.N.E.肾结石评分系统进行外部验证，评价该预测模型用于软性输尿管镜碎石术（flexible ureteroscopic lithotripsy，FURL）后结石清除率的有效性。方法： 收集2018年5月至2021年10月北京大学第三医院泌尿外科一期FURL治疗肾结石的连续病例资料，对改良S.T.O.N.E.肾结石评分系统进行评分，应用logistic回归模型分析改良S.T.O.N.E.评分及其变量与结石清除率的相关性，分别应用受试者工作特征曲线（receiver operating characteristic curve，ROC）和Hosmer-Lemeshow 拟合优度检验验证预测模型的区分度和校准度。结果： 本组396例FURL手术均成功完成，一期结石清除率为76.8%，改良S.T.O.N.E. 肾结石评分4~12分，中位数6分，评分结果与FURL术后SFR显著相关（OR=6.627，95%CI=3.620~12.131，P=0.001），FURL术后结石清除状态的ROC的AUC为0.778（95%CI=0.723~0.834），Hosmer-Lemeshow 拟合优度检验结果显示拟合度良好（χ²=0.824，P=0.844）。结论： 改良S.T.O.N.E.肾结石评分系统预测FURL术后的结石清除状态准确性高，有助于术前评估和临床决策。

Abstract:

Objective: To carry out an external validation of the modified S.T.O.N.E. nephrolithometry scoring system, and to evaluate its effectiveness in predicting the stone-free rate (SFR) of flexible ureteroscopic lithotripsy (FURL). Methods: Clinical data of 396 patients with nephrolithiasis undergoing FURL from May 2018 to October 2021 were collected, and the modified S.T.O.N.E. nephrolithometry scoring system was evaluated. The correlation of modified S.T.O.N.E. nephrolithometry scoring system scores and each variables with one-phase SFR was analyzed. The receiver operating characteristic curve (ROC) was computed to estimate the value of the predictive models, and Hosmer-Lemeshow goodness-of-fit test was used to examine the calibration of the prediction models. Results: All 396 cases of FURL operation were performed successfully, and the one-phase SFR was 76.8%. The median of the modified S.T.O.N.E. nephrolithometry scoring system score was 6 (4 to 12) in this cohort. The modified S.T.O.N.E. nephrolithometry scoring system score showed significant correlation with the postoperative SFR of FURL (OR=6.627, 95%CI=3.620-12.131, P=0.001). The area under curve of ROC in the state of stone clearance after FURL operation was 0.778 (95%CI=0.723-0.834). Hosmer-Lemeshow goodness-of-fit test showed that the modified S.T.O.N.E scoring system had satisfactory calibration in predicting SFR (χ²=0.824, P=0.844). Conclusion: The modified S.T.O.N.E. nephrolithometry scoring system can accurately predict postoperative stone-free status of FURL, and provide assistance in pre-operative evaluation and clinical decision-making.