Fourier Analysis of Corneal Irregular Astigmatism Due to the Anterior Corneal Surface in Dry Eye
Fourier Analysis of Corneal Irregular Astigmatism Due to the Anterior Corneal Surface in Dry Eye
复制标题
DOI：
10.1097/icl.0000000000000559
复制
发表时间：
2019-05-01
影响因子：
2.3
通讯作者：
Nishida, Kohji
中科院分区：
文献类型：
--
作者：
Koh, Shizuka;Maeda, Naoyuki;Nishida, Kohji
目的：目的：应用基于Placido环的角膜地形图仪（Placido-based topographer）和三维眼前段光学相干断层扫描（OCT）技术，对干眼症患者44例44眼和正常对照组20例20眼进行角膜前表面不规则散光的分析。角膜地形图数据使用基于Placido的地形图仪和OCT获得。角膜前表面中央3 mm区域的屈光度数据使用傅立叶谐波分析进行分解。球面，规则散光，和不规则散光（不对称和高阶不规则性）的角膜屈光不正组件从两个imaging models.Results：两个不对称和高阶不规则性值均显着大于对照眼的Placidobased地形图和OCT测量（所有P < 0.05）。在干眼症中，OCT测量的不对称性和高阶不规则性值显著小于基于Placido的地形图仪（均P < 0.001）。相比之下，在对照眼中，两种器械之间的这些参数没有显著差异。在干眼症，严重程度的浅点状角膜病变的中央角膜区域与不规则astigmatics.Conclusions：角膜不规则散光的量，量化使用傅立叶谐波分析，是显着高于干眼症比正常的眼睛。在干眼症受试者中，OCT和基于Placido的地形图仪获得的测量结果不同。因此，在尝试交替使用这些测量值时应谨慎。
Objectives: To evaluate corneal irregular astigmatism due to the anterior corneal surface using Fourier harmonic analysis with a Placido ring-based corneal topographer (Placido-based topographer) and three-dimensional anterior segment optical coherence tomography (OCT) in dry eyes.Methods: Forty-four eyes of 44 subjects with dry eye and 20 eyes of 20 normal control subjects were enrolled. Corneal topographic data were obtained using a Placido-based topographer and OCT. Dioptric data from the central 3-mm zone of the anterior corneal surface were decomposed using Fourier harmonic analysis. Spherical, regular astigmatism, and irregular astigmatism (asymmetry and higher-order irregularity) refractive error components of the cornea from the two imaging modalities were compared.Results: Both asymmetry and higher-order irregularity values were significantly greater in dry eyes than in control eyes for both the Placidobased topographer and OCT measurements (all P < 0.05). In dry eyes, measured values of asymmetry and higher-order irregularities were significantly smaller when obtained with OCT than with the Placido-based topographer (both P < 0.001). By contrast, these parameters were not significantly different between the two devices in control eyes. In dry eyes, severity of superficial punctate keratopathy in the central corneal region was correlated with irregular astigmatism.Conclusions: The amount of corneal irregular astigmatism, quantified using Fourier harmonic analysis, was significantly higher in dry eyes than in normal eyes. Measurements obtained with OCT and the Placido-based topographer differed in subjects with dry eyes. Therefore, caution should be practiced when trying to use these measurements interchangeably.