[Correlation between the increase in corneal higher-order aberrations and the control of children's myopic anisometropia after wearing orthokeratology lenses].

Objective: To explore the interocular differences in both the increase of corneal higher-order aberrations (HOAs) and axial length elongation, and the correlation between them after orthokeratology lens (OK lens) wear in children with myopic anisometropia. Methods: It was a prospective cohort study. From 2018 to 2019, 31 children with myopic anisometropia who were fitted with OK lenses initially in the Department of Ophthalmology of Peking University Third Hospital were enrolled, including 15 males (30 eyes) and 16 females (32 eyes). The age was (10.7±1.4) years. Before (baseline) and 12 months after wearing OK lenses, corneal aberrations, corneal relative refractive power (corneal RRP, the difference between peripheral corneal refraction and central corneal refraction) and axial length were measured using the Sirius combining a corneal topographer and a tomographer and an IOL-Master intraocular lens biometer in two eyes. Interocular differences in corneal aberrations, corneal RRP and axial length were analyzed by the paired t test and Wilcoxon rank sum test. The Pearson and Spearman correlation analyses were used to explore the correlation between the increase in corneal HOAs, corneal RRP and axial length elongation. Results: At 12 months after wearing OK lenses, 6 children were lost for follow-up, and the data of the remaining 25 children (50 eyes) were evaluated. With 3.0- and 6.0-mm measuring zones of the total cornea and the anterior surface, the increases in total corneal HOAs, coma, spherical aberration of higher myopic eyes were significantly more than fellow lower myopic eyes (all P<0.05). The corneal RRP with 2.0-mm and 2.5-mm radius in the upper cornea and 2.5-mm radius in the inferior cornea of higher myopic eyes were more than fellow lower myopic eyes (t=-2.06, -2.07, -2.42; P=0.05, 0.049, 0.023), but there was no significant interocular difference in corneal RRP in the horizontal meridian direction of the cornea (both the nasal and temporal sides of the cornea) (both P>0.05). The axial length elongation in higher myopic eyes was 0.14 (0.08, 0.20) mm, which was significantly less than that in the contralateral eyes [0.18 (0.14, 0.35) mm] (Z =-3.21, P= 0.001). The interocular difference in axial length decreased from 0.40 (0.34, 0.54) mm at baseline to 0.33 (0.24, 0.54) mm (Z =-3.21, P = 0.001). The increases in HOAs, coma and spherical aberration of the anterior corneal surface with 3.0-mm measuring zone and the increase in coma of the anterior corneal surface with 6.0-mm measuring zone were all negatively correlated with axial length elongation (r=-0.493, -0.606, -0.500, -0.307; P<0.05). But the corneal RRP had no significant correlation with axial length elongation (r=-0.092, -0.104, -0.230, -0.061; P>0.05). Conclusion: After 12 months of OK lens wear, interocular difference in axial length reduced significantly in children with myopic anisometropia, which was related to the larger increase in corneal HOAs of higher myopic eyes than fellow lower myopic eyes, especially coma.目的： 探究近视性屈光参差儿童配戴角膜塑形（OK）镜后，双眼角膜高阶像差增加量和眼轴长度增加量的差异以及两者的相关性。 方法： 前瞻性队列研究。连续收集2018年至2019年于北京大学第三医院眼科首次验配OK镜的31例近视性屈光参差儿童，其中男性15例（30只眼），女性16例（32只眼）；年龄（10.7±1.4）岁。戴镜前（基线）和戴镜后6、12个月时，分别对受试儿童双眼进行Sirius三维角膜地形图和光学生物指标检查，记录角膜高阶像差、角膜相对屈光力（角膜周边屈光力和角膜中央屈光力的差值）和眼轴长度。采用配对样本t检验和Wilcoxon秩和检验比较双眼各参数的差异，采用Pearson和Spearman相关分析探究角膜高阶像差增加量、角膜相对屈光力与眼轴长度增加量的相关性。 结果： 戴镜后12个月时失访6例，25例儿童（50只眼）纳入研究。总角膜和角膜前表面直径3.0和6.0 mm范围内，近视度数较高眼的总角膜高阶像差、彗差和球差的增加量均大于对侧眼（均P<0.05）。近视度数较高眼角膜上方距中央2.0和2.5 mm处、下方距中央2.5 mm处的角膜相对屈光力大于对侧眼（t=-2.06，-2.07，-2.42；P=0.05，0.049，0.023），但双眼角膜水平方向（角膜鼻侧和颞侧）的角膜相对屈光力差异无统计学意义（均P>0.05）。近视度数较高眼的眼轴长度增加量为0.14（0.08，0.20）mm，显著小于对侧眼的0.18（0.14，0.35）mm（Z=-3.21，P=0.001），双眼眼轴长度参差量从基线的0.40（0.34，0.54）mm减小为0.33（0.24，0.54）mm（Z=-3.21，P=0.001）。角膜前表面直径3.0 mm范围内的总角膜高阶像差、彗差和球差的增加量，以及角膜前表面直径6.0 mm范围内彗差的增加量，均与眼轴长度增加量呈负相关（r=-0.493，-0.606，-0.500，-0.307；P<0.05）；而角膜相对屈光力与眼轴长度增加量无显著相关（r=-0.092，-0.104，-0.230，-0.061；P>0.05）。 结论： 配戴OK镜后12个月，近视性屈光参差儿童双眼眼轴长度参差量减小，与近视度数较高眼的角膜高阶像差（尤其是彗差）的增加量大于对侧眼有关。.