ESWL治疗肾结石排空率的预测

Prediction of stone-free rate of renal stones after extracorporeal shock-wave lithotripsy

目的:了解影响肾结石体外冲击波碎石(Extracorporeal shock wave lithotripsy,ESWL)成功的因素,建立回归模型估计碎石后结石排空率。方法:1996年5月～2006年10月对1254例肾结石(结石直径<20mm)患者进行ESWL治疗,治疗效果在3个月随访时进行评价。碎石后比较无结石率与结石的特性,患者个人情况的相关性用方差检验进行分析,然后采用多变量回归分析方法进一步分析方差检验的有意义因素。结果:3个月随访时,ESWL后结石排空率为86.6。1.44(18例)患者结石未碎裂,7.97(100例)患者结石碎片未被清除,36.5患者接受三次ESWL治疗。方差检验分析发现患者年龄、性别、结石大小、结石位置、结石数目、结石性质、肾形状和先天不规则肾对碎石后结石的排空率均有影响。多变量分析排除了结石性质和患者性别作为影响无结石率的因素。根据这些因素,我们建立了ESWL后无结石率的回归分析模型。该模型的准确率为86.6。结论:结石大小、位置、数目、患者年龄、肾形状和先天性不规则肾是ESWL后结石清除率的影响因素。

Objective：To define prognostic factors that affect the success rate after extracorporeal shock-wave lithotripsy（ESWL）of renal calculi and to estimate the probability of stone-free status using a regression analysis model. Methods：Between May 1996 and October 2006, 1254 patients with renal stone（（20 ram） underwent ES- WL monotherapy. The results of treatment were evaluated after 3 months of follow-up. The stone-free rate was correlated with stone features and patient characteristics using the x^2 test . Factors found to be significant using the x^2 test were further analyzed using multivariate regression analysis. Results： At 3-month follow-up , the overall stone-free rate using ESWL monotherapy was 86.6 %. Failure to disintegrate the stones was observed in 1.44% of case （n = 18） and failure to clear the fragmented stones occurred in 7.97 % （n= 100）. Repeat ESWL was needed in 36.5% of cases. Using the x^2 test, patient age,stone size, location, number and nature, radiological renal picture and congenital real anomalies（P〈0. 001）had a significant impact on the stone-free rate . Multivariate analysis excluded stone nature from the logistic regression model while other factors maintained their statistically significant effect on success rate, indicating that they were independent predictors. A regression analysis model was designed to estimate the probability of stone-free status after ESWL with an accuracy 86.6%. Conclusions： Patient age, stone size, location and number, radiologlcal renal features and congenital renal anomalies are prognostic factors determining stone clearance after ESWL of renal calculi.