Kundel H L, Nodine C F, Thickman D, Toto L
Invest Radiol. 1987 May;22(5):417-22. doi: 10.1097/00004424-198705000-00010.
The contrast sensitivity of the retina is greatest in the center and decreases rapidly toward the periphery. Therefore, the detection of low-contrast lung nodules depends upon the manner in which the image is sampled by retinal receptors as eye fixations jump across the image during scanning. The scanning performance of two radiologists was compared with two computed models, a systematic and a random scanner. Although radiologists do not seem to have random scanning patterns, their coverage of the image was matched more closely by the random model. This suggests that radiologists employ a scanning strategy that is designed to cover the image of the lungs in a minimum time using the smallest possible visual field. The visual field size that is most effective in detecting nodules during search has a radius of 3.5 degrees visual angle. Nodule detection may be limited by basic neurologic constraints on human scanning performance.
视网膜的对比敏感度在中心区域最高，并朝着周边迅速下降。因此，低对比度肺结节的检测取决于在扫描过程中，当眼睛注视在图像上跳跃时视网膜感受器对图像的采样方式。将两名放射科医生的扫描表现与两种计算机模型进行了比较，一种是系统扫描模型，另一种是随机扫描模型。尽管放射科医生似乎没有随机扫描模式，但随机模型与他们对图像的覆盖匹配得更紧密。这表明放射科医生采用了一种扫描策略，旨在使用尽可能小的视野在最短时间内覆盖肺部图像。在搜索过程中检测结节最有效的视野大小，其视角半径为3.5度。结节检测可能受到人类扫描性能的基本神经学限制。
