儿童高度近视屈光因素分析

The refractive factors about children high myopia

目的探讨儿童高度近视眼的各屈光成份与近视发生的相关性。方法对38人73眼儿童高度近视患者分别进行散瞳验光,采集角膜不规则指数CIM、角膜形状系数SF与模拟角膜Simk1、Simk2,前房深度、晶体厚度、眼轴长度,并作角膜屈折力/眼轴长比值。结果屈光度为-6.0D～24.5D,平均球镜度为(10.23D±3.75)D;Simk1为(44.00±1.48)D,Simk2为(45.45±1.52)D,K值为42.86±9.09,角膜不规则指数CIM为0.73±0.35,角膜形状系数SF为0.27±0.08;前房深度(3.56±0.43)mm,晶体厚度(3.94±0.41)mm,眼轴长度(27.22±2.34)mm;角膜屈折力/眼轴长比值为1.66±0.15。屈光度与Simk2、前房深度、晶体厚度、眼轴长度、角膜屈折力/眼轴长比值间均有显著相关性,P<0.05;角膜不规则指数CIM、角膜形状系数SF与Simk1、Simk2均无统计意义的相关性,P>0.05。结论儿童高度近视患者以轴长为主,角膜屈光力与眼轴不匹配时便导致近视的发生和发展;儿童高度近视患者SF值小于正视眼,CIM大于正视眼,影响了成像质量,负反馈引起眼后段发育生长加快;高度近视儿童角膜屈光力的变化与角膜形状系数、角膜不规则指数的变化不相匹配,打破了眼球正常发育所需的协调性,可能引发了近视的产生。

Objective To evaluate the relationship between the refractive factors and development of the refraction in children high myopic group. Methods 73 eyes of 38 children high myopic group were analyzed,including refractive error,corneal irregularity measure(CIM)?shape factor(SF)?Simk1?Simk2,the anterior chamber depth?the lens thickness and the axial length;The ratio of Simk to the axial length were obtained.Results The refractive error were -6.0D～24.5D,SE were (10.23D±3.75)D;The corneal irregularity measure(CIM) were 0.73±0.35,the shape factor(SF) were 0.27±0.08?Simkl were (44.00±1.48)D?Simk2 were (45.45±1.52)D,the Simk were 42.86±9.09;The anterior chamber depth were (3.56±0.43)mm,the lens thickness were (3.94±0.41)mm and the axial length were (27.22±2.34)mm;The ratio of Simk to the axial length were 1.66±0.15.There were significant correlations among the refractive error and Simk2?the anterior chamber depth?the lens thickness?the axial length and Simk/the axial length(P<0.05);There were no correlations among the corneal irregularity measure(CIM)?shape factor(SF)and Simk1?Simk2(P>0.05).Conclusions Axial myopia is more than refractive myopia in children high myopic group.If corneal refraction is not match to axial length,myopia may be occur;SF in children high myopic group is smaller than SF in emmetropic group,while CIM in emmetropic group is smaller than CIM in children high myopic group,the imagation affected,the axial length may be become longer and longer,The change of corneal refraction is not match to the change of SF or CIM in children high myopic group,the coordination broken,myopia may be occur.