CT值对ESWL成功率预测的研究

Study on prognosis of ESWL based on Hounsfield units in CT scan

目的了解非增强螺旋CT的结石CT值对预测上尿路结石体外冲击波碎石（ESWL）后结石排空率的价值。方法对35例结石大小在0.5-1.5cm需行ESWL的上尿路单发结石患者先行非增强螺旋CT检查，并测定结石CT值，经ESWL后复查B超及腹平片检查，随访3个月，根据碎石屑残留与否，将35例患者分结石排空组及结石残留组（将残留碎石屑〈3mm者归入排空组）。统计学分析两组间患者的基本特征，结石CT值、能量冲击次数。结果结石排空者25例（71.4％），结石残留组10例（28.6％），总的结石排空组与残留组的结石平均CT值分别为（650±185）HU和（950±282）HU（t=5.463，P〈0.01），差异有统计学意义。结论非增强螺旋CT的结石CT值能预测体内上尿路结石ESWL后结石的粉碎率和排空率。CT值低者ESWL后结石容易被粉碎和易于排空；CT值高者结石的粉碎率和排空率明显下降。此类患者则可考虑选择输尿管镜下取石碎术、经皮肾穿刺取石碎术。

Objective To study the value of the Hounsfield units, which were gotten in non-contrast helical computerized tomography （NCHCT） of upper urinary tract calculi, in prognosticating of the stone-free rate after extracorporeal shock wave lithotripsy （ESWL）. Method A total of 35 case of single upper urinary tract calculi 0.5-1.5 cm in size underwent NCHCT measuring the Hounsfield units before ESWL to treat the calculi. Type-B ultrasonic scan and plain abdominal radiograph were reviewed regularly in the 3 months after treatment. The 35 cases were divided into 2 groups of stone-free and stone-left （The cases with the biggest stone fragment sized less than 3 mm were divided into the stone-free group）. The main conditions of the patients, the Hounsfield units the power used in ESWL and times of shock waves were statistically compared between the 2 groups. Result 25 cases were stone-free （71.4%）, 10 cases had residual stones （28.6%）. The mean Hounsfield units of the stone-free group and stone-left group were respectively （650±185） HU and （950±282） HU （t=5.463,P〈0.01）. Conclusion Hounsfield units got from NCHCT can be used to prognose the result of ESWL. The stones with lower Hounsfield units can be crushed by ESWL and eliminated more easily. The stones with higher Hounsfield unit have lower successful rate. While, ureteroscopic lithotripsy and percutaneous nephrolithotripsy should be considered.