CT扫描对复杂性肾结石经皮肾镜取石术后疗效的预测价值

目的探讨cT扫描对复杂性肾结石经皮肾镜取石术（PCNL）后疗效的预测价值。方法对296例接受PCNL治疗复杂性肾结石患者的临床资料进行回顾性研究，分析术前CT扫描相关指标，如HU值、结石大小、结石位置、结石x线通透性等与术后结石清除率的关系，同时对HU值预测复杂性肾结石术后临床疗效进行评价及总结。结果根据结石清除率分组，多因素方差分析发现结石X线通透性、结石位置、HU值以及结石大小等指标均为影响结石清除率的因素（P〈0．05）。利用ROC曲线确定HU值诊断结石完全清除与否的阈值，发现最佳诊断点为688．4，低于此值，结石清除率明显降低。对结石成分与结石清除率的关系进行了探讨，发现含钙结石清除率高于其他成分的结石，但两组之间无统计学差异（P〉0．05）；同时发现HU值与术中出血量之间存在明显的正相关关系（P〈0．05）。结论术前CT扫描明确结石大小、结石位置以及HU值测定对复杂性肾结石PCNL术后临床疗效具有预测价值；术前明确结石的CT表现，采取恰当的手术方式能进一步提高碎石效率。

Application of CT scan for prediction of the outcome of complex renal calculi after percutaneous nephrolithotomy

Objective To evaluate the application value of preoperative CT scan for prediction of the outcome of complex renal calculi after percutaneous nephrolithotomy （PCNL）. Methods Clinical data of 296 cases with complex renal calculi treated with PCNL were analyzed retrospectively. Nomograms including HU value, stone size, stone location and the opacity of stone determined by preoperative CT scan were assessed to comfirm the relation with stone free rate （SFR）, also, application value of HU was determined for prediction of the outcome of complex renal calculi after PCNL. Results In the logistic regression analysis, the HU value, stone size, stone location, the opacity of stone were found to be independent predictors of the SFR （P〈O.05）. ROC determined the cutoff point of HU value for predicting SFR at 688.4. SFR markly decreased with a HU value under this threshold. Analysis of stone composition suggested SFR of calcium stone was higher than other types, but no significant difference was found （P〉0.05）. There was a positive correlation between blood loss and HU values （P〈0.05）. Conclusions HU value, stone size, stone location determined by preoperative CT scan were the parameters affecting PCNL outcome in complex renal calculi. Definitive estimation of CT presentation can direct the treatment option and improve the efficiency of stone free rate.