摘要
目的通过实验取得有关数据，制作Ｘ线屏片组合体系的观测者操作特性（ｒｅｃｅｉｖｅｒｏｐｅｒａｔｉｎｇｃｈａｒａｃｔｅｒｉｓｔｉｃ，ＲＯＣ）曲线，并检测最大信息量（Ｉｍａｘ）。方法用直径２ｍｍ的丙烯树脂实球和空心球各１００个，在３种Ｘ线屏片组合体系，即扁平颗粒技术（新型屏片体系）、ＣａＷＯ４屏天津胶片、ＢａＦＣｌ∶Ｅｕ屏天津胶片所形成的影像，由３位医务工作者，在照度为６０００Ｌｘ观片灯上，用ｙｅｓ（Ｓ）－ｎｏ（Ｎ）２×２判断矩阵法取得数据，描绘ＲＯＣ曲线，并计算Ｉｍａｘ。结果（１）扁平颗粒技术得到的照片上检测的Ｉｍａｘ最大；对稀土ＢａＦＣｌ∶Ｅｕ屏天津片检测的Ｉｍａｘ最小。（２）对直径２ｍｍ的空心球丙烯树脂所形成的微小信息检测的Ｉｍａｘ值较直径２ｍｍ实球的为大。（３）工作２５年以上医师检测的Ｉｍａｘ值最大。结论（１）应用Ｘ线屏片组合体系所形成照片斑点少的扁平颗粒技术，检测到的Ｉｍａｘ值大，能提供给医师信息量大的Ｘ线照片影像。（２）应用稀土增感屏组成的屏片组合体系，形成照片斑点多，检测到的Ｉｍａｘ值小。
Purpose To draw the ROC curve and obtain the maximum information according to the experimental data of Xray screenfilm systems. Methods 100 acrylic resin balls and 100 acrylic resin hollow balls 2mm in diameter were used to generate images on three screenfilm combinations: flat grain (new screenfilm system), CaWO4 screenTianjin film and BaFCl:Eu screenTianjin film. The ball images were analysed by two doctors and one student on a 6000 lux luminosity view box. The ROC curves were drawn and the maximum information (Imax) was calculated from the 2×2 evaluation matrix data got by means of answering yes(S)no(N). Results (1)The Imax measured on new screenfilm system was the largest, and that on the BaFCl screenTianjin film was the smallest. (2)The information quantity formed by 2mm in diameter hollow balls was greater. (3) The Imax measured by a doctor with over25year experience was the largest. Conclusion (1) The Imax from new screenfilm which had fewer film mottles was the largest.(2) Imax from the rare earth screenfilm system was the smallest.
出处
《中华放射学杂志》
CAS
CSCD
北大核心
1998年第8期567-570,共4页
Chinese Journal of Radiology
关键词
X线胶片
X线增感屏
放射摄影术
ROC曲线
Xray film Xray intensifying screens Radiography Evaluation studies Receiver operating characteristic (ROC) curve
