轴率比在儿童中低度近视诊断的应用
Diagnostic Value of Axial to Corneal Curvature Ratio in Children with Low Myopia and Moderate Myopia

目的：评价眼轴与角膜曲率半径的比值(轴率比)在诊断低度近视与中度近视的应用。方法：回顾性分析586例2015年12月至2018年9月期间就诊于福建省第二人民医院眼科的低中度近视儿童的眼轴、平均角膜曲率半径等，计算轴率比，睫状肌麻痹后主觉验光的等效球镜度数(spherical equivalent, SE)。低度近视为？0.50~？3.00 D，中度近视？3.00~？6.00 D。以低度近视的95%百分位数作为低度近视的上限，行正态性检验、秩相关分析及ROC曲线分析。结果：低度近视组与中度近视组轴率比和SE均呈非正态分布，低度近视组轴率比为(3.062 ± 0.098)，与轴率比 = 3有统计学差异(P < 0.01)；低度近视组SE为(？1.58 ± 0.75) D；中度近视组轴率比为(3.205 ± 0.126)，与轴率比=3有统计学差异(P < 0.01)；中度近视组SE为(？4.17 ± 0.78) D；两组之间轴率比有统计学差异(P < 0.01)。以低度近视轴率比的95%参考值3.199作为区分低、中度近视的临界值与诊断近视的金标准睫状肌麻痹下主觉验光相比，轴率比诊断中度近视的灵敏度为0.630，特异度为0.950，准确度为89.1%，Kappa系数为0.619，ROC曲线下面积为0.876 (P < 0.01)。结论：轴率比在低度近视和中度近视诊断中具有一定价值。
AIM: To evaluate the application of the ratio of axial radius to corneal curvature in the diagnosis of low and moderate myopia. METHODS: This retrospective clinical study included 586 children with refractive errors, aged 8 to 14 years old, who were admitted to the second people’s Hospi-tal of Fujian Province from December 2015 to September 2018. All subjects underwent meas-urements for distance vision, axial length (AL), the average radius of the corneal curvature (CR), etc. Then the AL/CR radio and spherical equivalent (SE) from cycloplegic refraction were calcu-lated. ？3.00 D ≤ SE ≤ ？0.50 D was defined as low myopia, ？6.00 D ≤ SE < ？3.00 D was defined as moderate myopia. The 95% percentile of low myopia was taken as the upper limit of low myo-pia. And the normality test, rank correlation analysis and ROC curve analysis were performed. RESULTS: In low myopia group, the AL/CR radio was (3.062 ± 0.098), that is statistical different from three, SE in low myopia group was (？1.58 ± 0.75) D (P < 0.01). In moderate myopia group, AL/CR radio was (3.205 ± 0.126), and is statistically different from three, SE in low myopia group was (？4.17 ± 0.78) D (P < 0.01). There was statistical difference between two groups. The critical value, 95% reference value of AL/CR radio in low myopia, compared with gold standard ciliary palsy in the diagnosis of myopia, the sensitivity, specificity and accuracy of AL/CR radio (3.199) in the diagnosis of moderate myopia were 0.630, 0.950, 89.1%, the Kappa coefficient was 0.619. The area under the ROC curve was 0.876 (P < 0. 01). CONCLUSION: The AL/CR ratio has certain value in the diagnosis of low myopia and moderate myopia.