1Department of Ophthalmology, the Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou 325027, China 2Department of Ophthalmology, the Quzhou Hospital of Wenzhou Medical University, Quzhou 324000,China
Abstract:Objective: To calculate the school-aged children's anterior corneal Q values of different regions with the tangential radius of curvature acquired from the Pentacam anterior segment analyzer and analyze its distribution characteristics in different refractive status groups. Methods: A case series study was conducted. One hundred and ninty-two school-aged children were recruited from September 2018 to October 2019 in the Department of Ophthalmology of the Second Affiliated Hospital of Wenzhou Medical University. Only the right eyes were selected as objects of research. The patients were grouped by the magnitude of the spherical equivalent (SE) refractive error of the right eye: moderate myopia, low myopia, emmetropia, low hyperopia and moderate hyperopia. The Pentacam anterior segment analyzer was used to measure the cornea. The anterior corneal Q values of the nasal (315°-45°), superior (45°-135°), temporal (135°-225°) and inferior (225°-315°)region were calculated by the tangential radius with linear regression equation. Data was analyzed using ANOVA and Pearson correlation analysis. Result: The mean Q values of the nasal, superior, temporal and inferior region were -0.50±0.13, -0.62±0.15, -0.31±0.10 and -0.42±0.18. The difference of them was statistically significant (F=215.19, P<0.001). Only the nasal and inferior Q values were found significantly different among the different refracive groups (F=6.00, P<0.001; F=2.95, P=0.022).The relationship between Q values and SE was negative (r=-0.38, P<0.001; r=-0.16, P=0.031). No difference was found for superior and temporal Q values among the different refracive groups respectively. By further analysis, we revealed the Q values difference between the nasal-temporal region was significantly different among the different refracive groups (F=10.40, P<0.001). A trend toward higer the Q values difference between the nasal-temporal region was found as the SE increased. Pearson analysis showed the relationship between them was statistically significant (r=-0.42, P<0.001). Conclusion: The anterior corneal Q values of different regions of school-aged children's eyes were different. The nasal Q values, inferior Q values and the Q values difference between the nasaltemporal region were all significantly different among the different refracive groups and correlated with SE. It's critically important to considere the anterior corneal Q values of different regions when correctting refraction for different refractive children.
郭燕, 琚霄慧, 金卡露, 等.. 不同屈光状态学龄期儿童角膜前表面区域Q值的研究[J]. 中华眼视光学与视觉科学杂志, 2022, 24(6): 441-446.
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