Department of Ophthalmology and Visual Science, Hiroshima University Graduate School of Biomedical and Health Sciences, 1-2-3 Kasumi, Minamiku, Hiroshima, 7348551, Japan.
Int Ophthalmol. 2021 Mar;41(3):805-813. doi: 10.1007/s10792-020-01633-9. Epub 2020 Nov 13.
To evaluate the fovea in nanophthalmic eyes using spectral domain optical coherence tomography (SD-OCT) and OCT angiography (OCTA), and to investigate the relationship between the macular microstructure and visual acuity.
This is a retrospective case series of five nanophthalmic patients. The foveal avascular zone (FAZ) area was measured in superficial and deep vascular layers with OCTA. The thickness of the inner retinal layer (IRL) was measured with SD-OCT. The ratio of the foveal and parafoveal IRL thickness (fIRL/pIRL ratio) was calculated. The relationship between these parameters and visual acuity was then investigated.
Eight eyes were identified as nanophthalmic with a mean axial length of 17.19 ± 1.44 mm (range: 15.71 to 19.88 mm). The mean best-corrected visual acuity (BCVA) in the logarithm of the minimum angle of resolution (logMAR) was 0.12 ± 0.18 (range: - 0.18 to 0.40). OCTA showed that FAZs were either absent or undeveloped in the superficial and deep capillary plexuses. Two patients did not show any visual impairments despite small FAZ and a shallow foveal depression. Although the BCVA was significantly correlated with the deep FAZ size, it did not correlate with the superficial FAZ size, axial length, or fIRL/pIRL ratio. However, the refractive error, axial length, and deep FAZ size were all significantly correlated with the fIRL/pIRL ratio.
The FAZs were commonly found to be small in the superficial and deep capillary plexuses. Although the deep FAZ size correlated with visual acuity, it is unclear whether the retinal microstructure and the FAZ size are responsible for the visual impairments observed in the same individuals.
利用谱域光相干断层扫描（SD-OCT）和 OCT 血管造影（OCTA）评估小眼球的黄斑部，并探讨黄斑部微观结构与视力之间的关系。
这是一项回顾性的小眼球病例系列研究，共纳入 5 名小眼球患者。使用 OCTA 测量浅层和深层血管层的黄斑无血管区（FAZ）面积。使用 SD-OCT 测量内视网膜层（IRL）的厚度。计算黄斑部和旁黄斑部 IRL 厚度的比值（fIRL/pIRL 比值）。然后研究这些参数与视力之间的关系。
8 只眼被确定为小眼球，平均眼轴长度为 17.19±1.44mm（范围：15.71 至 19.88mm）。平均最佳矫正视力（BCVA）在最小分辨角对数（logMAR）中为 0.12±0.18（范围：-0.18 至 0.40）。OCTA 显示浅层和深层毛细血管丛中的 FAZ 要么不存在，要么发育不全。尽管 FAZ 较小且黄斑部较浅，但有 2 名患者视力不受影响。尽管 BCVA 与深层 FAZ 大小显著相关，但与浅层 FAZ 大小、眼轴长度或 fIRL/pIRL 比值均无相关性。然而，屈光不正、眼轴长度和深层 FAZ 大小均与 fIRL/pIRL 比值显著相关。
浅层和深层毛细血管丛中的 FAZ 通常较小。尽管深层 FAZ 大小与视力相关，但尚不清楚视网膜微观结构和 FAZ 大小是否是导致同一患者视力下降的原因。
