Eldaly Zeiad, Soliman Wael, Sharaf Mohamed, Reyad Ali Natag
Department of Ophthalmology, Assiut University, Assiut, Egypt.
Alforsan Center, Assiut, Egypt.
J Ophthalmol. 2020 Aug 19;2020:8281459. doi: 10.1155/2020/8281459. eCollection 2020.
To provide quantitative measurements for the foveal avascular zone (FAZ) and to describe its morphological characteristics by optical coherence tomography angiography (OCT-A).
Cross-sectional observational case series.
Healthy volunteers were recruited and evaluated using Triton-DRI SS-OCT Angiography. A 4.5 × 4.5 mm square was evaluated by OCT-A center around the fovea. Superficial and deep capillary plexus were identified, and different quantitative measurements were conducted along with categorization of the FAZ pattern.
Eighty-two eyes (41 volunteers) were evaluated. Mean age was 30.59 ± 7.6 years (23-42 years). Mean subcentral retinal thickness was 200.1 ± 5.66 um (192-210 um). The number of terminal vessels was variable (range, 8-11). Mean maximum terminal vessel-to-vessel intervening distance was 527.8 ± 60.3 um (471-674 um). Mean minimum terminal vessel-to-vessel intervening distance was 296.7 ± 45.8 um (233-373 um). Mean maximum horizontal diameter of FAZ (superficial) was 716.17 ± 124.09 um, while mean maximum vertical diameter of FAZ (superficial) was 667.76 ± 131.28 um. Mean maximum horizontal diameter of FAZ (deep) was 823.19 ± 144.92 um, while mean maximum vertical diameter of FAZ (deep) was 794.03 ± 150.28 um. OCT-A detected different FAZ patterns; horizontally oval configuration in 32 eyes (39%), rounded configuration in 24 eyes (29.3%), pentagon configuration in 14 eyes (17.1%), and vertically oval and nonspecific configuration in 6 eyes each (7.3%).
OCT-A could efficiently provide both quantitative and qualitative assessment of normal FAZ; such characterizations were difficult by standard FAZ assessment procedures like FFA.
通过光学相干断层扫描血管造影（OCT-A）对黄斑无血管区（FAZ）进行定量测量，并描述其形态特征。
横断面观察性病例系列。
招募健康志愿者并使用Triton-DRI SS-OCT血管造影进行评估。以黄斑为中心，通过OCT-A评估一个4.5×4.5毫米的正方形区域。识别浅层和深层毛细血管丛，并进行不同的定量测量以及FAZ模式分类。
评估了82只眼（41名志愿者）。平均年龄为30.59±7.6岁（23 - 42岁）。视网膜中心下平均厚度为200.1±5.66微米（192 - 210微米）。终末血管数量各异（范围为8 - 11条）。终末血管间平均最大间距为527.8±60.3微米（471 - 674微米）。终末血管间平均最小间距为296.7±45.8微米（233 - 373微米）。FAZ（浅层）平均最大水平直径为716.17±124.09微米，而FAZ（浅层）平均最大垂直直径为667.76±131.28微米。FAZ（深层）平均最大水平直径为823.19±144.92微米，而FAZ（深层）平均最大垂直直径为794.03±150.28微米。OCT-A检测到不同的FAZ模式；水平椭圆形构型32只眼（39%），圆形构型24只眼（29.3%），五边形构型14只眼（17.1%），垂直椭圆形和非特异性构型各6只眼（7.3%）。
OCT-A能够有效地对正常FAZ进行定量和定性评估；而通过荧光素眼底血管造影（FFA）等标准FAZ评估程序很难做到这些特征描述。
