Discipline of Medical Radiation Sciences, Faculty of Health Science, University of Sydney, Sydney, NSW, Australia.
Br J Radiol. 2013 Jan;86(1021):20110812. doi: 10.1259/bjr.20110812.
Objective The current study aims to establish whether detection of solitary pulmonary nodules can be improved by inverting the grey scale of posteroanterior (PA) chests. Methods 30 PA chest images were presented on 2 occasions to 16 senior radiologists on either primary or secondary class displays in the standard or inverted mode. 15 images within each group contained a single nodule positioned in a range of anatomical sites. A receiver operating characteristic (ROC) methodology was used to explore differences between the presentation modes. Results Improved ROC scores were evident with inverted (Az 0.77) compared with standard (Az 0.73) (p=0.02) images; however, this difference was seen only with the primary displays. The benefits seen are most likely owing to increased nodule luminance with the inverted images, particularly when using primary displays. Conclusion This study demonstrates that the inverted image can offer advantages in lung nodule detection over the standard presentation mode when images are viewed on high-specification viewing systems. The study has demonstrated that there is an improvement in the detectability of lung nodules on an inverted image with a primary display monitor that is not evident with secondary displays. This is likely to be the result of increased nodule luminance on primary displays when images are presented in the inverted mode.
目的 本研究旨在探讨反转前后位（PA）胸部 X 线片的灰度是否能提高对孤立性肺结节的检出率。
方法 将 30 张 PA 胸部 X 线片在标准或反转模式下，先后两次呈现在 16 位资深放射科医师的初级或次级显示屏上。每组 15 张图像均包含一个位于不同解剖部位的单个结节。采用受试者工作特征（ROC）方法探索不同呈现模式之间的差异。
结果 与标准（Az 0.73）图像相比，反转（Az 0.77）图像的 ROC 评分明显提高（p=0.02）；然而，这种差异仅见于初级显示屏。这种优势可能归因于反转图像中结节的亮度增加，尤其是在使用初级显示屏时。
结论 本研究表明，在高规格的观察系统上，与标准呈现模式相比，反转图像在肺结节检测方面具有优势。本研究表明，在使用初级显示屏时，反转图像的可检测性有所提高，而在次级显示屏上则不明显。这可能是由于反转模式下，初级显示屏上的结节亮度增加所致。
