摘要
目的用实验方法研究显示器(CRT)性能对影像识读的影响。方法(1)用ST-86LA型光度计对2台显示器(CRT1、CRT2)的亮度特性、均匀特性、对比度特性进行测试与比较,并绘制其受试者特性曲线(ROC)。(2)对模拟病变信号进行摄影,获取18幅实验影像,请3位影像诊断医师分别在2台显示器上进行识读,累计识读结果,绘制ROC曲线并进行分析。结果(1)CRT1、CRT2的最大亮度分别为102和128cd/m2,可辨识的最大密度胶片影像为D=1·51和1·81;边缘处的亮度分别为中心亮度的93·14%和92·97%;大面积对比度分别为48·12、41·25,小面积对比度为10·96和15·09。整体性能,CRT2优于CRT1。(2)ROC曲线下面积(Az):大信号纵隔部Az1=0·8564、Az2=0·8806,差异无统计学意义(χ2=0·2916,P>0·05);肺野Az1=0·7967、Az2=0·8478,差异无统计学意义(χ2=1·3495,P>0·05);小信号纵隔部Az1=0·7876、Az2=0·8338,差异无统计学意义(χ2=0·5516,P>0·05);肺野Az1=0·6964、Az2=0·7958,差异具有统计学意义(χ2=4·9947,P<0·05)。结论(1)显示器性能对大信号识读影响小、对小信号识读影响大。(2)高密度影像受显示器性能影响大、低密度影像受显示器性能影响小。(3)在识读载有小信号的高密度所成影像时,为保证影像识读质量,应配备高性能的显示器。
Objective To study the influence of display＇s performance on image identification by means of experiment. Method （ 1 ） The brightness, equality, and contrast qualities of two displays （ CRT1 and CRT2 ） were tested and compared and the quality curves were protracted using ST-86LA photometer. （2） The analog abnormal signals were photographed to get 18 films which were viewed on two displays by three doctors, then the results were added up for protracting and analyzing ROC curve. Results （ 1 ） The maximal brightness of CRT1 and CRT2 was 102 cd/m^2 and 128 cd/m^2 , the maximal cognizable density film image was D = 1.51 and D = 1.81, brightness at verge was 93. 14% and 92.97% of that at the center respectively; The contrast of large area was 48.12 and 41.25, and small one was 10. 96 and 15. 09. The overall performance of CRT2 was superior to that of CRT1. （2） The area Az in ROC curve ： Big signal of mediastinum Az1 = 0. 8564, Az2 = 0. 8806, showing no significant difference（ X^2 = 0. 2916, P 〉 0. 05） ; lung field Az1 = 0. 7967, Az2 = 0. 8478 （ X^2 = 1. 3495, P 〉 0. 05）. Small signal of mediastinum Az1 = 0. 7876, Az2 =0. 8338 （ X^2 = 0. 5516, P 〉 0.05） ; lung field Az1 = 0. 6964, Az2 = 0. 7958, showing significant difference（X^2 =4.9947, P〈0.05）. Conclusion （1）The effect of display＇s performance on reading big signal is small and its effect on reading small signal is big. （2）The influence of display on image of high density film is big, while the effect on low density is small. （3）To ensure image＇s identification, the display with high performance should be equipped when identifying high density film with small signals.
出处
《中华放射学杂志》
CAS
CSCD
北大核心
2005年第11期1213-1216,共4页
Chinese Journal of Radiology
