[关键词]
[摘要]
目的:探讨不同程度近视眼在不同调节状态下OCT(optic coherence tomography,OCT)测量的眼前段结构的变化。
方法:招募60例近视患者,年龄:18~39岁,按近视程度分为轻中度近视组和高度近视组,用眼前段OCT对测试眼分别在调节放松(0D)、诱发3.00D和5.00D调节三种调节状态下进行眼前段扫描分析,分别测量不同调节状态下角膜后表面曲率(posterior corneal curvature,PCC)、前房深度(anterior chamber depth,ACD)、晶状体厚度(lens thickness,LT)和暗瞳直径的大小,采用重复测量的方差分析比较不同调节状态下上述参数的差异以及不同程度近视在相同调节状态下各参数的差异。
结果:在调节放松情况下,轻中度近视组眼前段OCT测得的平均PCC,ACD,LT和瞳孔直径(pupil diameter,PD)分别为:6.92±0.91mm,2.67±0.19mm,4.17±0.21mm和6.21±0.56mm; 高度近视组的平均PCC,ACD,LT和PD分别为:6.83±0.81mm,2.92±0.23mm,4.22±0.24mm和5.95±0.42mm。轻中度近视组与高度近视组在PCC和LT方面的差异均无显著性(t=0.401,-0.742; P=0.690,0.461),而ACD方面,高度近视组显著大于轻中度近视组(t=-4.637,P=0.000),高度近视组的PD则小于轻中度近视组(t=2.011,P=0.049)。两不同程度近视组中,在0.0D,3.00D和5.00D三种不同的调节状态下测得的PCC的差异均无显著性(F=0.084,0.047; P=0.920,0.954); ACD随调节的逐渐增大而均变浅(F=19.44,8.455; P=0.000,0.001); LT随调节的逐渐增大而均增厚(F=31.149,15.245; P=0.000,0.000); PD随调节的逐渐增大而均减小(F=83.634,53.429; P=0.000,0.000)。
结论:眼前段OCT可以定量观察近视眼调节时眼前段各部分的变化,高度近视眼前房较轻中度近视深,而瞳孔较小; 发生不同程度调节时,角膜的形状相对稳定,LT,ACD及PD随调节量的增加其变化量逐渐增大。
[Key word]
[Abstract]
AIM: To evaluate anterior segment changes during accommodation in different degree of myopia with OCT.
METHODS: Sixty myopes with the age from 18 to 39 years were enrolled in this study and were divided into two groups: low to moderate myopia group(>-6.0D), and high myopia group(≤-6.0D). Anterior segment measurements were performed by anterior segment optic coherence tomography(OCT)under three different accommodative state of relax(0.0 D), 3.00D and 5.00D. The posterior corneal curvature(PCC), anterior chamber depth(ACD), lens thickness(LT), pupil diameter(PD)were compared at different accommodative state using repeated measures ANOVA.
RESULTS:Low to moderate myopia group comprised 32 myopes with the mean age 29.34±4.65 years, mean spherical equivalent -3.72±1.05D; High myopia group comprised 28 myopes with the mean age 29.57±5.89 years, mean spherical equivalent -7.05±0.85D; With the accommodation relaxed(0D), there was no difference between the low to moderate myopia group and high myopia group both in PCC and LT, ACD was 2.92±0.23mm in high myoia and 2.67±0.19mm in low to moderate myopia(t=-4.637, P=0.000). Pupil diameter was 6.21±0.56mm in low to moderate myopia and 5.95±0.42mm in high myopia(t=2.011, P=0.049). With the accommodation increased, ACD decreased significantly, LT increased significantly, and PD decreased significantly in both groups(all P<0.05). The PCC has no significant change during accommodation in both groups(all P>0.05).
CONCLUSION: Anterior segment OCT can find the alteration of ACD, LT and PD with accommodation. During accommodation, the cornea is stable. However, with the accommodation increased, ACD, greater changes happened in LT and PD using anterior segment OCT.
[中图分类号]
[基金项目]
中国广东省医学科学技术研究基金资助项目(No.A2012244)