Ocular Surface and Cornea Unit, Department of Ophthalmology, Oftalmar, Hospital Internacional Medimar, Alicante, Spain; Foundation for the Visual Quality (FUNCAVIS, Fundación para la Calidad Visual), Alicante, Spain; Department of Optics, Pharmacology and Anatomy, University of Alicante, Spain.
Ocular Surface and Cornea Unit, Department of Ophthalmology, Oftalmar, Hospital Internacional Medimar, Alicante, Spain.
Cont Lens Anterior Eye. 2014 Feb;37(1):49-54. doi: 10.1016/j.clae.2013.07.006. Epub 2013 Jul 30.
To define a range of normality for the vectorial parameters Ocular Residual Astigmatism (ORA) and topography disparity (TD) and to evaluate their relationship with visual, refractive, anterior and posterior corneal curvature, pachymetric and corneal volume data in normal healthy eyes.
This study comprised a total of 101 consecutive normal healthy eyes of 101 patients ranging in age from 15 to 64 years old. In all cases, a complete corneal analysis was performed using a Scheimpflug photography-based topography system (Pentacam system Oculus Optikgeräte GmbH). Anterior corneal topographic data were imported from the Pentacam system to the iASSORT software (ASSORT Pty. Ltd.), which allowed the calculation of the ocular residual astigmatism (ORA) and topography disparity (TD). Linear regression analysis was used for obtaining a linear expression relating ORA and posterior corneal astigmatism (PCA).
Mean magnitude of ORA was 0.79 D (SD: 0.43), with a normality range from 0 to 1.63D. 90 eyes (89.1%) showed against-the-rule ORA. A weak although statistically significant correlation was found between the magnitudes of posterior corneal astigmatism and ORA (r=0.34, p<0.01). Regression analysis showed the presence of a linear relationship between these two variables, although with a very limited predictability (R(2): 0.08). Mean magnitude of TD was 0.89D (SD: 0.50), with a normality range from 0 to 1.87D.
The magnitude of the vector parameters ORA and TD is lower than 1.9D in the healthy human eye.
定义向量参数眼内残余散光（ORA）和地形图像差（TD）的正常值范围，并评估它们与正常健康眼中的视觉、屈光、前、后角膜曲率、角膜厚度和角膜容积数据的关系。
本研究共纳入 101 例年龄在 15 至 64 岁之间的连续正常健康眼 101 例。在所有病例中，均使用基于 Scheimpflug 摄影的地形图系统（Oculus Optikgeräte GmbH 公司的 Pentacam 系统）进行全面的角膜分析。从前角膜地形图系统导入 Pentacam 系统数据到 iASSORT 软件（ASSORT Pty. Ltd.），该软件可以计算眼内残余散光（ORA）和地形图像差（TD）。采用线性回归分析得出 ORA 与后角膜散光（PCA）的线性关系表达式。
平均 ORA 大小为 0.79D（标准差：0.43），正常值范围为 0 至 1.63D。90 只眼（89.1%）表现为逆规散光。后角膜散光和 ORA 大小之间存在弱但具有统计学意义的相关性（r=0.34，p<0.01）。回归分析显示这两个变量之间存在线性关系，但预测能力非常有限（R²：0.08）。TD 的平均大小为 0.89D（标准差：0.50），正常值范围为 0 至 1.87D。
健康人眼的 ORA 和 TD 向量参数大小小于 1.9D。
