A Qualitative Study on Diagnosing Myopia Using the Ratio of Axial Length to Corneal Radius of Curvature
Abstract
Objective: To investigate the influence of axial length (AL), corneal curvature (CR), and the ratio of axial length to corneal radius of curvature (AL/CR) on myopia in children, and to evaluate the accuracy and specificity of AL/CR in diagnosing myopia in children. Methods: A cross-sectional study was conducted. A total of 200 children (400 eyes) aged 6–12 years were recruited from the ophthalmology outpatient clinic of Fuling District People’s Hospital from December 2022 to December 2023. AL, CR, and AL/CR were measured, and comprehensive optometry was performed under cycloplegia, with the results recorded in spherical equivalent (SE) form. Results: A total of 200 subjects (400 eyes) were included in this study, of which 330 eyes (82.50%) were myopic. No significant differences in CR were observed among different refractive groups, while significant differences were noted in SE, AL, and AL/CR. The AL and AL/CR ratios were higher in myopic eyes compared to emmetropic and hyperopic eyes. Using cycloplegia as the gold standard, SE in the myopia group was correlated with AL, AL/CR, and CR, with stronger correlations observed with AL and AL/CR. An AL/CR value > 3 demonstrated a sensitivity of 0.918, specificity of 0.786, misdiagnosis rate of 0.214, missed diagnosis rate of 0.082, and accuracy of 89.5% in diagnosing myopia. Conclusion: AL and AL/CR values are highly correlated with SE, with the strongest correlation observed in the myopia group. The AL/CR value exhibits high diagnostic value in determining myopia in children.
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