散光相关性屈光不正近视化状况

Evaluation of myopization in astigmatism-related ametropia

目的 探究散光相关性屈光不正近视化进程的状况.方法 病例系列研究.选取4～6岁散光儿童210例（412眼）,男114例,女96例.检测其最佳矫正视力、眼轴长度、扩瞳验光度数（1%硫酸阿托品滴眼液）等指标,随访24个月.应用SAS 9.2统计软件中的混合效应模型,分析不同度数和轴向的散光对球性屈光不正度数和眼轴长度的影响.结果 2年内,210例儿童中散光度数越高,眼轴长度和近视度数增加越显著（F分别为7.380、10.636,P均＜0.01）;超高度组明显重于轻、中、高度组（P均＜0.05）,而轻度与中度组差异不明显;眼轴长度和近视度数增加值在轻度组分别为（0.19±0.10）mm、（0.78±0.79）D,中度组为（0.20±0.14）mm、（0.94±0.79）D,高度组为（0.33±0.14）mm、（1.36±0.68）D,超高度组为（0.38±0.12）mm、（1.60±0.58）D.2年内,散光轴向对儿童眼轴长度和近视度数存在影响（F分别为12.351、12.384,P均＜0.01）;顺规性散光组近视度数增加最少,斜轴性散光组眼轴长度增加最多（P＜0.05）,而斜轴和逆规组眼轴、近视程度增加值组间差异无统计学意义：眼轴长度和近视度数增加值在顺规组分别为（0.20±0.17）mm、（0.74±0.49）D,逆规组为（0.28±0.17）mm、（1.26±0.98）D,斜轴组为（0.43±0.20）mm、（1.61±0.74）D.结论 在眼睛近视化过程中,散光度数越高,近视化进程越快：斜轴散光对近视进展的影响较顺规散光、逆规散光大.故在近视防治工作中要充分考虑到散光对近视化的影响.关键词：散光;近视化;眼轴;

Objective To evaluate the myopization of astigmatism-related ametropia. Methods Case series study. Two hundred and ten children （412 eyes）, 114 boys and 96 girls, aged 4 to 6 years with astigmatism were involved in the study. The children were examined 3 times over 24 months, measuring best corrected visual acuity, axial length, refraction and astigmatism after pupil dilation （with 1% atropine） and monitoring other indicators to analyze the difference between the type and degree of astigmatism. A mixed model in SAS 9.2 software program was used for analysis.Results Axial length （AXL） and spherical diopters of myopic astigmatism in ametropic children increased with the amount of astigmatism during the 24 months （F=7.380, 10.636, P〈0.01 for both）.Myopia was aggravated more seriously in the group with very high amounts of astigmatism than in the mild to severe groups （P〈0.05 for all）, while no significant difference was found between the mild and moderate groups. The mean values for the increased AXL and spherical amounts of myopia were （0.19±0.10）mm and （0.78±0.79）D in the mild group, （0.20±0.14）mm and （0.94±0.79）D in the moderate group, （0.33±0.14）mm and （1.36±0.68）D in the high group, and （0.38±0.12）mm and （1.60±0.58）D in the very high group. During myopic progression over the two years, the with-the-rule astigmatism group was the slowest to progress, with mean increases of （0.20±0.17）mm and （0.74±0.49）D of AXL and spherical degrees of myopia, respectively, followed by the against-the-rule group with mean increases of （0.28±0.17）mm and （1.26±0.98）D. The mean increases for the oblique group were （0.43±0.20）mm and （1.61±0.74）D, which showed the fastest myopization progress. No significant difference was found between the against-the-rule and oblique groups, but they both had significant increases in myopization （F=12.351 and 12.384, P〈0.01 for both）. Conclusion This study shows that myopia progresses much faster with high and very high astigmatism than with mild to moderate astigmatism. Myopia progresses the fastest with oblique astigmatism and with-the-rule astigmatism has the slowest progression. Therefore, it is necessary to take astigmatism into consideration in the control of the myopization process.