儿童近视进展与眼底血流及脉络膜厚度的关系

目的：探讨儿童近视进展过程中眼底血流及脉络膜厚度的变化。方法：前瞻性研究。招募2018 年7—9月就诊于温州医科大学附属眼视光医院的低中度近视儿童，随访观察其1年的屈光度数及眼轴长度（AL）变化，以评估其近视进展。同期采用扫频源光学相干断层扫描血流成像（SS-OCTA）技术进行黄斑区3 mm×3 mm扫描。采用扫频光学相干断层成像（SS-OCT）技术进行黄斑区6 mm×6 mm放射状扫描，并采集随访观察1年前后受检者右眼黄斑中心凹，中心凹上、下、鼻、颞侧的脉络膜厚度以及浅层和深层视网膜及脉络膜毛细血管层的血流密度。取受检者右眼数据进行统计分析。采用配对t检验、Pearson相关性及简单线性回归进行统计学分析。结果：共纳入47例（47眼）受检儿童，男21例，女26例，年龄为（11.1±1.3）岁。1年后随访，平均等效球镜度（SE）由（-2.59±0.93）D增至（-3.09±0.96）D（t=11.12，P<0.001）；AL由（24.75±0.86）mm增长至（24.91±0.84）mm（t=12.25，P<0.001）；脉络膜厚度由（238±54）μm减小至（231±55）μm（t=2.67，P=0.011）；视网膜浅层、深层及脉络膜毛细血管层血流密度均出现明显下降（t=6.66，P<0.001；t=3.38，P=0.002；t=3.18，P=0.003）。视网膜浅层、深层血流密度变化量与近视度数增加量之间存在线性相关（r=0.35，P=0.02；r=0.37，P=0.01）。结论：近视儿童在近视进展过程中，脉络膜厚度变薄，视网膜及脉络膜血流密度降低，推测此类眼底变化可能在近视进展过程中起到一定作用。

The Relationship between Myopia Progression,Fundus Blood Flow and Choroidal Thickness in Children

Objective: To investigate the effects of myopia progression on fundus blood flow and choroidal thickness (CT) in children. Methods: This was a prospective study. The subjects were recruited from the Eye Hospital, Wenzhou Medical University from July 2018 to September 2018. Cycloplegic autorefraction and axial length (AL) were measured at baseline and at 12-month visits. Radial lines (6 mm×6 mm) and angio (3 mm×3 mm) scans centered on the macula were obtained using swept-source optical coherence tomography (SS-OCT) and SS-OCT angiography. CT was measured in the fovea, superior, inferior, nasal and temporal areas of the fovea. Flow density was recorded using self-provided software in thesuperficial retinal layer, deep retinal layer and choroid capillary layer. A paired t-test, Pearson correlation test and simple linear regression were used to analyze the results. Results: A total of 47 myopic children (47 eyes) aged 11.1±1.3 years that included 21 males and 26 females were enrolled. After one year, the AL and SE of the subjects increased significantly 24.75±0.86 mm increased to 24.91±0.84 mm, t=12.25, P<0.001; -2.59±0.93 D increased to -3.09±0.96 D, t=11.12, P<0.001. Compared with baseline data,the CT became significantly thinner, from 238±54 μm to 231±55 μm (t=2.67, P=0.011), and blood flow density of the superficial and deep retina and choroid decreased significantly after 1 year (t=6.66, P<0.001;t=3.38, P=0.002; t=3.18, P=0.003). There was a linear correlation between the changes in blood flow of the superficial and deep retina and the changes in diopter (r=0.35, P=0.02; r=0.37, P=0.01). Conclusions:CT becomes thin and retinal and choroid blood flow density decrease significantly during the progression of myopia in children. It is speculated that these fundus changes may play a role in the progression of myopia.