医学成像系统显示器性能的对比研究

The comparative study of the performance of display devices in medical imaging system

目的通过对不同医学成像系统显示器性能的研究，定量分析显示器性能在显示临床图像时对图像解读的影响。方法使用亮度及照度测量器L100和美国医学物理师协会（AAPM）所提供的显示器性能测试图对3种类型显示器（球面、纯平、液晶显示器）的亮度响应进行测试，并与AAPM所提供的评价标准比较。管电流为100mA，管电压为80kVp，曝光时间分别为6、10、12、16ms的条件下使用数字x线摄影系统（DR）对CDRAD2．0对比度细节体模进行模拟胸部的曝光，记录体模表面入射剂量，计算其图像质量因子，应用ANOVA检验方法进行统计学分析。结果球面显示器亮度最大值为170cd／m^2，亮度比为257。纯平显示器亮度最大值为59．305cd／m^2，亮度比为99。液晶显示器亮度最大值为231．73cd／m^2，亮度比为350。3种显示器的亮度响应和亮度对比响应均超出AAPM所设定的允许偏差范围。液晶显示器上显示图像所获得的图像质量因子（IQF）值与其他2种显示器上获得的IQF值之间差异有统计学意义（P〈0．05）。结论测试性能好的液晶显示器所显示的图像质量相对好些。

Objective To analyze the effects of three different display devices on the interpretation of imaging data in medical imaging system. Methods The luminance-meter L100 and the test patterns provided by the American Association of Physicists in Medicine （AAPM） were used to assess the performance of three display devices （the spherical, flat panel and liquid crystal display devices）. The corresponding luminance response was compared with the reference criteria provided by AAPM Task Group 18 （AAPM TG18 ）. DR chest photography was taken on CDRAD2. 0 contrast-detail phantom using the following experimental parameters： 100 mA, 80 kVp, and the exposure times for 6, 10, 12, and 16 ms. After each exposure, the surface dose of phantom was recorded and the image quality factor （IQF） was calculated. Statistical analysis of IQF was performed using ANOVA. Results The maximum luminance values in the spherical, flat panel and liquid crystal display devices were 170, 59 and 231 cd/m^2 and the luminance ratio was 257, 99 and 350 respectively. There was a significant difference in the IQF bewteen the liquid crystal display device and other two display devices. Conclusion The liquid crystal display device has the better image quality.