目的 探讨常规CT鉴别诊断尿酸与非尿酸结石的价值.方法 搜集泌尿外科手术后结石60枚,将其用蒸馏水清洗干净,自然晾干、编号,放于猪肾内并记录位置,将埋有结石的猪肾标本放于组织模型中行常规CT扫描,分别测量结石软组织窗和骨窗CT值,红外光谱法结石分析结果为参照,评估常规CT鉴别诊断尿酸与非尿酸结石的价值.结果 红外光谱分析结果显示,60枚泌尿系结石中纯尿酸结石8枚,非尿酸结石52枚.纯尿酸结石和非尿酸结石的软组织窗与骨窗平均CT值比较,差异均无统计学意义(P＞0.05);纯尿酸结石的软组织窗及骨窗平均CT值均低于非尿酸结石(P＜0.05).以软组织窗平均CT值＜550 HU为阈值诊断纯尿酸结石,其灵敏度为87.50%,特异度为94.23%,准确度为93.33%,阳性预测值为70.00%,阴性预测值为98.00%,正确指数为0.82.结论 常规CT可鉴别诊断大部分纯尿酸结石与非尿酸结石区分,为临床治疗和预防尿酸结石提供参考.%Objective To explore the value of conventional CT in the differential diagnosis of uric acid and non uric acid calculus. Methods A total of 60 stones,collected from urological procedures,were numbered and placed into pig kidney with recording positions after being cleaned up by distilled water and dried in the air.The pig kidney specimens with buried stones were put into the tissue model for a conventional CT scanning to measure the CT values of soft tissue window and bone window of the stones respectively.Using the analysis result of infrared spectrometry for the stone specimens as a reference,the value of conventional CT in the differential diagnosis of uric acid and non uric acid calculus was assessed.Results The result of infrared spectrometry revealed that there were 8 pure uric acid stones and 52 non uric acid stones out of 60 urinary calculi.No significant difference was found in the average CT value between soft tissue window and bone window of the pure uric acid stone or the non uric acid stone(P＞0.05);and the average CT values of soft tissue window and bone window of the pure uric acid stone were lower than those of the non uric acid stone(P＜0.05).The sensitivity,specificity,accuracy, positive predictive value,negative predictive value,and correct index for average CT threshold value of soft tissue window ＜550 HU in the diagnosis of the pure uric acid stones were 87.50%,94.23%,93.33%,70.00%,98.00%,and 0.82,respectively.Conclusion Most of the pure uric acid stones can be distinguished from the non uric acid stones by conventional CT,which can be used as a reference for the clinical treatment and prevention of uric acid calculus.
展开▼
