University of Maryland School of Medicine (A.N.L.), Baltimore, MD; and Department of Ophthalmology (I.S.K.M., W.M.M., S.Z.M., J.L.A.), University of Maryland Eye Associates, University of Maryland, Baltimore, MD.
Eye Contact Lens. 2021 Sep 1;47(9):494-499. doi: 10.1097/ICL.0000000000000818.
To determine the repeatability of corneal measurements from anterior segment optical coherence tomography (AS-OCT) images using ImageJ software in healthy eyes compared with eyes with keratoconus.
Anterior segment OCT images of 25 eyes from 14 healthy subjects and 25 eyes from 15 subjects with keratoconus between the ages of 20 and 80 years were evaluated. Two trained observers used ImageJ to measure the central corneal cross-sectional area and anterior and posterior corneal arc lengths. MedCalc statistical software was used to generate the intraclass correlation coefficient (ICC) and Bland-Altman plots (BAPs) for observer measurements.
Observer measurements of the central corneal cross-sectional area and anterior and posterior corneal arc lengths yielded an ICC >0.7. The ICC comparing the 3 parameters ranged from 0.75 to 0.84 for the control and 0.96 to 0.98 for the keratoconus group. No systematic proportional bias was detected by the BAPs. There were minimal differences between the 2 observer's measurements, with a mean of the difference of 0.3 mm2, 0 mm, and 0 mm, for the 3 measurements, respectively.
This study suggests that ImageJ software is a repeatable and reliable tool in the analysis of corneal parameters from AS-OCT images among patients with keratoconus and may be applicable to AS-OCT imaging protocol development, an area of active keratoconus research.
使用 ImageJ 软件比较健康眼与圆锥角膜眼中前节光学相干断层扫描（AS-OCT）图像的角膜测量重复性。
评估了年龄在 20 至 80 岁之间的 14 名健康受试者的 25 只眼和 15 名圆锥角膜受试者的 25 只眼的前节 OCT 图像。两名经过培训的观察者使用 ImageJ 测量中央角膜横截面积和前、后角膜弧长。使用 MedCalc 统计软件生成观察者测量的组内相关系数（ICC）和 Bland-Altman 图（BAP）。
观察者对中央角膜横截面积和前、后角膜弧长的测量得出的 ICC>0.7。对照组 3 个参数的 ICC 范围为 0.75 至 0.84，圆锥角膜组为 0.96 至 0.98。BAP 未检测到系统比例偏差。两名观察者测量值之间差异较小，3 项测量的差异平均值分别为 0.3mm2、0mm 和 0mm。
本研究表明，ImageJ 软件是一种可重复且可靠的工具，可用于分析圆锥角膜患者的 AS-OCT 图像中的角膜参数，并且可能适用于 AS-OCT 成像方案的开发，这是圆锥角膜研究的一个活跃领域。
