螺旋CT扫描预测体内尿酸结石的临床价值

Diagnosis of uric acid calculi by helical computed tomography

目的研究螺旋CT对患者体内尿酸结石的预测价值。方法2005年12月至2009年12月,对391例上尿路结石患者在治疗前行螺旋CT平扫,测结石CT值,定量分析各种治疗方法所获取结石的化学成分,应用统计学分析,找出纯尿酸结石与非纯尿酸结石的CT值范围。结果33例纯尿酸结石(尿酸含量大于70%)与358例非尿酸结石及纯度小于70%的尿酸结石的CT值差异有统计学意义(P<0.05);在CT软组织窗测得的结石平均CT值500HU以下为标准诊断纯尿酸结石,其灵敏度为93.94%,特异度为96.93%,阳性预测值为73.81%,阴性预测值为99.43%。结论结石的CT值可作为诊断尿酸结石的一种方法,CT值小于500HU的结石多考虑为纯尿酸结石。

Objective To evaluate helical computed tomography （CT） in the prediction of uric acid calculi.Methods Form December 2005 to December 2009,391 cases of urinary calculi underwent helical CT scan before stone removal.The average CT values were measured.The chemical composition of those calculi was analyzed.Statistical analysis was performed to find the CT value range of different uric acid stones.Results There was a statistically significant difference between pure uric acid stones and other stones.Using 〈500 HU as criteria,pure uric acid stones were diagnosed with the sensitivity of 93.94%,specificity of 96.93%,positive predictive value of 73.81% and negative predictive value of 99.43%.Conclusions The CT value of stone can be used as a diagnostic method of uric acid stones.Stone with CT value less than 500 HU is highly suggested as a pure uric acid stone.