中国光学, 2020, 13 (4): 770, 网络出版: 2020-08-17
角膜塑形术后角膜面形分析及周边离焦研究 下载: 684次
Analysis of the corneal surface and peripheral defocus after orthokeratology
角膜塑形镜 角膜分区 周边离焦 分区算法 眼模型 orthokeratology lens division of cornea peripheral defocus partition algorithm eye model
摘要
本文提出了一种新的角膜面形分析方法,不仅消除了角膜本体厚度对塑形后角膜面形分析的影响,同时也能体现塑形后角膜的不对称性。在角膜前表面高度数据分析中引入基准参考面,以消除角膜本体厚度的影响,进而将塑形后的角膜前表面划分为光学区、转换区和边缘区。分析表明,角膜塑形后的光学区口径为(1.9±0.27) mm,曲率半径为(8.32±0.38) mm;转换区口径为(6.56±0.38) mm,曲率半径为(7.48±0.55) mm;边缘区的曲率半径为(10.49±1.83) mm。角膜塑形后的转换区水平方向屈光能力小于竖直方向的屈光能力,鼻侧屈光能力大于颞侧屈光能力,上侧屈光能力大于下侧屈光能力。利用所得参数建立半定制化的眼模型,对眼模型进行分析,结果表明:角膜塑形后周边呈近视性离焦,各方向的离焦呈非对称性分布,符合临床表现。
Abstract
A new method of corneal shape analysis method is proposed. It not only eliminates the influence of corneal thickness on the shape of cornea after orthokeratology, but also reflects the asymmetry of a cornea. A reference surface is introduced into the analysis of the height data of the anterior surface of the cornea to eliminate the influence of corneal thickness. On the basis of above, anterior surface of the cornea is divided into the optical zone, transition zone and peripheral zone. The results show that the optical zone diameter is (1.9±0.27) mm, and the curvature radius is (8.32±0.38) mm; the transition zone diameter is (6.56±0.38) mm, and the curvature radius is (7.48±0.55) mm; the curvature radius of the peripheral zone is (10.49±1.83) mm. After orthokeratology, the horizontal refraction of the transition zone is lower than its vertical refraction. The refraction of the nasal side is greater than that of the temporal side and the refraction of the upper side is greater than that of the lower side. A semi-customized eye model is established based on the obtained parameters and the results show that its peripheral defocus is myopic after orthokeratology and its defocus is asymmetrical in each direction, which is consistent with clinical observations.
刘宝凯, 刘永基, 谢培英, 郭曦, 谷健达, 于浩. 角膜塑形术后角膜面形分析及周边离焦研究[J]. 中国光学, 2020, 13(4): 770. Bao-kai LIU, Yong-ji LIU, Pei-ying XIE, Xi GUO, Jian-da GU, Hao YU. Analysis of the corneal surface and peripheral defocus after orthokeratology[J]. Chinese Optics, 2020, 13(4): 770.