Singapore Eye Research Institute, Singapore.
Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
Br J Ophthalmol. 2020 Jul;104(7):917-923. doi: 10.1136/bjophthalmol-2019-314769. Epub 2019 Oct 4.
To assess specific layers of the choroid in highly myopic young adults and to examine their associations with levels of myopia.
We recruited 51 young myopes (n=91 eyes) from the Singapore Cohort of Risk Factors for Myopia cohort. We performed standardised optical coherence tomography (OCT) and OCT angiography imaging and developed a novel segmentation technique assessing choroidal layers' thickness (overall choroidal thickness (CT), medium-vessel choroidal layer (MVCL) thickness, large-vessel choroidal layer (LVCL)) and vasculature (choroidal vessel density (%), choroidal branch area (CBA, %) and mean choroidal vessel width (MCVW, mm)).
We found that eyes with extreme myopia (EM) had thinner vascular layers compared with high myopia (HM), that is, LVCL (36.0±1.5 vs 39.2±1.2 µm, p=0.002) and MVCL (185.5±5.7 vs 198.2±4.6 µm, p=0.014). Overall CT was thinnest in the nasal and inferior quadrants in EM (nasal: 157.1±9.6 vs 187.2±8.3 µm, p<0.001; superior: 236.6±11.1 vs 257.0±9.5 µm, p=0.02; temporal: 228.0±10.6 vs 254.3±8.8 µm, p=0.012; and inferior quadrant: 198.7±10.0 vs 239.8±8.3 µm, p=<0.001) when compared with HM. We also observed significantly more vessel branching in eyes with EM as compared with eyes with HM (CBA, 10.2%±0.7% vs 9.95%±0.8%, p=0.018).
The novel segmentation technique and introduced choroidal parameters may serve as new biomarkers to study disease conditions in myopia.
评估高度近视的年轻成年人脉络膜的特定层，并研究它们与近视程度的关系。
我们从新加坡近视危险因素队列研究中招募了 51 名年轻近视患者（n=91 只眼）。我们进行了标准的光学相干断层扫描（OCT）和 OCT 血管造影成像，并开发了一种新的分割技术来评估脉络膜层的厚度（总脉络膜厚度（CT）、中血管脉络膜层（MVCL）厚度、大血管脉络膜层（LVCL）厚度）和血管（脉络膜血管密度（%）、脉络膜分支面积（CBA，%）和平均脉络膜血管宽度（MCVW，mm））。
我们发现，极高度近视（EM）眼的血管层比高度近视（HM）眼更薄，即 LVCL（36.0±1.5 比 39.2±1.2 μm，p=0.002）和 MVCL（185.5±5.7 比 198.2±4.6 μm，p=0.014）。EM 眼的总 CT 在鼻侧和下方象限最薄（鼻侧：157.1±9.6 比 187.2±8.3 μm，p<0.001；上方：236.6±11.1 比 257.0±9.5 μm，p=0.02；颞侧：228.0±10.6 比 254.3±8.8 μm，p=0.012；下方象限：198.7±10.0 比 239.8±8.3 μm，p<0.001），与 HM 眼相比。我们还观察到，EM 眼的血管分支明显多于 HM 眼（CBA，10.2%±0.7%比 9.95%±0.8%，p=0.018）。
新的分割技术和引入的脉络膜参数可以作为研究近视疾病状态的新生物标志物。
