隐匿性近视儿童黄斑区脉络膜厚度随时间变化的规律

Changes of macular choroidal thickness with time in children with occult myopia

目的 探讨隐匿性近视儿童黄斑区脉络膜厚度随时间的变化规律。方法 选择2021年2月至2022年2月在我院就诊的视力及小瞳下眼屈光正常的4-6岁儿童60例作为研究对象。根据眼轴长度及角膜曲率将儿童分为2组,隐匿性近视组30例60眼,对照组(正常儿童)30例60眼。采用非接触性IOL Master测量双眼眼轴长度;谱域光学相干断层成像(SD-OCT)将黄斑分为以中央凹为中心的三个同心圆(ETDRS网格),共九个分区:中心凹(1 mm内)、内环(>1~3 mm)和外环(>3~6 mm),内环和外环区域被细分为上方、下侧、鼻侧和颞侧,测量各分区儿童脉络膜厚度。采用重复测量方差分析两组儿童黄斑区脉络膜厚度,组间比较采用独立样本t检验,组内两两比较采用最小显著差法,相同测量时间点组间差异采用独立样本t检验。结果 两组儿童性别、年龄、基线等效球镜度比较,差异均无统计学意义(均为P>0.05);隐匿性近视组儿童基线眼轴长度较对照组长,角膜曲率较对照组小,差异均有统计学意义(均为P<0.01)。在初诊及随访3、6、9、12个月时,隐匿性近视组儿童黄斑中心凹、内环上方、内环鼻侧、内环下方、内环颞侧、外环上方、外环鼻侧、外环下方、外环颞侧脉络膜厚度均小于对照组,随着时间的推移两组儿童脉络膜厚度均有逐渐变薄趋势,差异均有统计学意义(均为P<0.01)。结论 隐匿性近视儿童黄斑各个分区脉络膜厚度均随时间的变化呈现不同程度变薄的趋势,且较正常儿童变薄速度更快。

Objective To explore the changes of macular choroidal thickness with time in children with occult myopia.Methods Sixty children aged 4-6 years with normal visual acuity and refraction under small pupils admitted to our hospital from February 2021 to February 2022 were selected in this study.According to the axial length(AL)and corneal curvature(CC),these children were divided into the occult myopia group(30 children,60 eyes)and the control group(30 children,60 eyes).The binocular AL was measured by non-contact IOL Master.The macula was divided into three concentric circles(ETDRS grid)centered on the central fovea and nine zones in total by the spectral domain optical coherence tomography:central fovea(<1 mm),inner ring(>1-3 mm)and outer ring(>3-6 mm).The inner and outer rings were subdivided into superior,inferior,nasal and temporal zones,respectively,and the choroidal thickness in each zone was measured.The macular choroidal thickness was analyzed by the repeated measures ANOVA.The independent-samples t-test was performed for comparison between groups and comparison of measurements at the same time point between groups,and the least significant difference method was adopted for pairwise comparison within groups.Results There was no significant difference in sex,age and baseline spherical equivalent between the two groups(all P>0.05).The baseline AL in the occult myopia group was larger than that in the control group,while the CC was smaller than that in the control group(both P<0.01).At the first visit and return visits 3,6,9 and 12 months later,the choroidal thickness in the central fovea,superior,inferior,nasal and temporal zones in the inner and outer rings in the occult myopia group were lower than those in the control group.With the passage of time,the choroidal thickness in the two groups tended to decrease(all P<0.01).Conclusion The choroid in each macular zone of occult myopia children tends to become thinner with time,at a rate faster than that of normal children.