北京市羊坊店学区两个年级组小学生远视力和眼轴的关系

Correlation between distance visual acuity and axial length in the children of two grades from Yangfangdian District in Beijing

目的观察不同年级小学生远视力和眼轴长度相关性,为近视防治寻找监控点。设计横断面调查。研究对象北京市羊坊店学区全部小学的一年级、四年级学生2970例。方法采用标准对数视力表测量远视力,光学相干生物测量仪(IOLMaster)测量眼轴长度。取右眼测量值统计分析。主要指标远视力,眼轴长度,视力不良比例。结果一年级组(年龄6.44±0.52岁)、四年级组(9.25±0.46岁)眼轴长分别为(22.73±0.72)mm(n=1270)、(23.66±0.93)mm(n=1672)(P=0.000);一年级组、四年级组远视力分别为(1.02±0.26)(n=1282)、(0.86±0.42)(n=1494)(P=0.000)。一年级组眼轴长与远视力无明显相关性(r=0.019,P=0.495);四年级组眼轴长与远视力呈明显负相关性(r=-0.425,P=0.000)。眶轴长>24.00 mm的学生,视力不良率最高。结论小学生视力和眼轴发育随着年龄的增加而改变,小学生眼轴超过24 mm是近视防治监控点。

Objective To observe the association between distance visual acuity（DVA） change and axial length（AL） growth in different school-children, and to find out a key to monitoring for prevention and cure to myopia. Design Cross section survey. Participants 2970 students from the grade 1 and 4 of all primary schools in Yangfangdian district in Beijing. Methods The DVA of the pupils was measured using standard logarithmic visual acuity chart and the AL was measured with IOLMaster. The statistical analyses were performed using data of the right eye only. Main Outcome Measures Distance visual acuity, axial length, percentage of poor sight. Results Students of grade 1 （mean age 6.44±0.52 years） and grade 4 （mean age 9.25±0.46 years） were examined. The mean AL of students was 22.73±0.72 mm in grade 1 （n=1270）, significantly shorter than that of grade 4 （23.66±0.93 mm） （n=1672）（P=0.000）. The mean DVA of students in grade 1 （n=1282） and 4 （n=1494） was 1.02±0.26 and 0.86±0.42 respectively, the difference was statistically significant （P=0.000）. Linear regression analyses indicated that there was no correlation between AL and DVA in grade 1 students （r=0.019, P= 0.495）. However, significantly negative correlation in grade 4 students was demonstrated （r=-0.425, P=0.000）. Students that AL〉24.00 mm had the largest rates of poor sight. Conclusions We found that DVA and AL growth were affected by age. Students with AL longer than 24 mm were the key population to be monitored for prevention of myopia.