计算机X线摄影能量减影与直接数字摄影对胸部软组织病变检测能力比较

Application value of computed radiography energy subtraction in detecting pulmonary soft-tissue：comparison with direct digital radiography

目的 比较计算机X线摄影能量减影技术（ES-CR）与直接数字摄影技术（DR）对肺内软组织信号的探测能力.方法 应用胸部放射学体模和X线摄影统计学体模摄取ES-CR和DR影像,由6位放射科医师用5等级判别法各自独立阅读影像,编写程序对观察结果进行受试者操作特性曲线（ROC）分析.收集28例病理证实小肺癌患者的胸部DR影像和ES-CR影像,由3位放射科医师一起做出诊断,分析其真阳性率的差异性.结果 体模影像的ROC分析,ES-CR和DR的Az值分别为0.727和0.827,差异有统计学意义（Z=2.96,P＜0.05）.28例小肺癌两成像系统的差异也有统计学意义（x2=5.14,P＜0.05）.结论 用DR诊断的真阳性率要高于ES-CR.ES-CR对胸部软组织信号的检出能力尚不如DR.

Objective To compare the efficiency of computed radiography energy subtraction （ES-CR） with direct digital radiography （DR） in detecting the pulmonary soft-tissue signals.Methods The adult chest phantom including TRG was imaged by ES-CR and DR separately and was estimated by 6 radiologists with 5-value-differentiation method. ROC was used to analyze the performance of two systems. Images of DR and ES-CR of 28 patients with small lung cancer were diagnosed by 3 radiologists. Results The area under the ROC curves was 0. 727 in ES-CR and 0.827 in DR （Z= 2.96,P ＜ 0. 05）. 28 small lung cancer patients were significantly different between two systems （x2 = 5.14,P ＜0. 05）. Conclusions The true positive proportion of DR might be higher than that of ES-CR. ES-CR is inferior to DR in detecting pulmonary soft-tissue signals.