CT系统目测分辨率与系统调制传递函数相关性分析

摘要

Objective To evaluate the correlation between the visual resolution and the modulation transfer function (MTF) of CT system. Methods scanned the resolution test module in CT test phantom, obtained the MTF and visual resolution of CT system. Results the resolution which human eyes can clearly distinguish corresponds to spatial frequencies where MTF is 10％; the visual limited resolution corresponds roughly to spatial frequencies where MTF is between 5％ and 2％. Conclusion The correlation analysis for MTF and visual resolution of CT can effectively reflect relationship between the (rue detectability of CT system and human visual acuity and help to raise the level of our work.%目的对CT系统MTF(调制传递函数)和目测分辨率之间的关系进行研究.方法扫描CT测试体模中分辨率测试模块,获得系统MTF和目测空间分辨率.结果当MTF为10%时所对应的空间频率与清晰分辨的线对卡分辨率一致,当MTF为2%～5%时对应的空间频率与目测极限分辨率接近.结论通过CT系统MTF和目测分辨率相关关系研究,可以客观反映系统对细节识别能力与人眼识别能力之间的对应关系,从而提高CT质量控制水平.