Centre for Ophthalmology and Visual Science, The University of Western Australia, Perth, Australia.
Lions Eye Institute, 2 Verdun St, Nedlands, Perth, WA, 6009, Australia.
Sci Rep. 2023 May 9;13(1):7550. doi: 10.1038/s41598-023-33490-8.
An adequate blood supply to meet the energy demands is essential for any tissue, particularly for high energy demand tissues such as the retina. A critical question is: How is the dynamic match between neuronal demands and blood supply achieved? We present a quantitative assessment of temporal and spatial variations in perfusion in the macular capillary network in 10 healthy human subjects using a non-invasive and label-free imaging technique. The assessment is based on the calculation of the coefficient of variation (CoV) of the perfusion signal from arterioles, venules and capillaries from a sequence of optical coherence tomography angiography images centred on the fovea. Significant heterogeneity of the spatial and temporal variation was found within arterioles, venules and capillary networks. The CoV values of the capillaries and smallest vessels were significantly higher than that in the larger vessels. Our results demonstrate the presence of significant heterogeneity of spatial and temporal variation within each element of the macular microvasculature, particularly in the capillaries and finer vessels. Our findings suggest that the dynamic match between neuronal demands and blood supply is achieved by frequent alteration of local blood flow evidenced by capillary perfusion variations both spatially and temporally in the macular region.
为满足能量需求，充足的血液供应对任何组织都是至关重要的，特别是对视网膜等高能量需求组织而言。一个关键问题是：神经元需求和血液供应之间的动态匹配是如何实现的？我们使用一种非侵入性和无标记的成像技术，对 10 名健康人类受试者黄斑毛细血管网络中的灌注的时间和空间变化进行了定量评估。该评估基于从以黄斑为中心的一系列光相干断层扫描血管造影图像中计算出的动脉、静脉和毛细血管的灌注信号的变异系数（CoV）。在动脉、静脉和毛细血管网络内发现了显著的空间和时间变化异质性。毛细血管和最小血管的 CoV 值明显高于较大血管。我们的研究结果表明，黄斑微血管的每个组成部分，特别是毛细血管和更细的血管内，空间和时间变化的异质性都很大。我们的研究结果表明，通过在黄斑区域内的毛细血管灌注的空间和时间变化来频繁改变局部血流，从而实现了神经元需求和血液供应之间的动态匹配。
