绘制人周边视网膜血管网络图以了解毛细血管中的血流变异性。

Mapping the human parafoveal vascular network to understand flow variability in capillaries.

机构信息

Department of Optometry and Vision Sciences, The University of Melbourne, Victoria, Australia.

Department of Surgery, The University of Melbourne, Victoria, Australia.

出版信息

PLoS One. 2023 Oct 13;18(10):e0292962. doi: 10.1371/journal.pone.0292962. eCollection 2023.

Abstract

Capillary flow is known to be non-homogenous between vessels and variable over time, for reasons that are poorly understood. The local properties of individual vessels have been shown to have limited explanatory power in this regard. This exploratory study investigates the association of network-level properties such as vessel depth, branch order, and distance from the feeding arteriole with capillary flow. Detailed network connectivity analysis was undertaken in 3 healthy young subjects using flood-illuminated adaptive optics retinal imaging, with axial depth of vessels determined via optical coherence tomography angiography. Forty-one out of 70 vessels studied were of terminal capillary type, i.e. fed from an arterial junction and drained by a venous junction. Approximately half of vessel junctions were amenable to fitting with a model of relative branch diameters, with only a few adhering to Murray's Law. A key parameter of the model (the junction exponent) was found to be inversely related to the average velocity (r = -0.59, p = 0.015) and trough velocity (r = -0.67, p = 0.004) in downstream vessels. Aspects of cellular flow, such as the minimum velocity, were also moderately correlated (r = 0.46, p = 0.009) with distance to the upstream feeding arteriole. Overall, this study shows that capillary network topology contributes significantly to the flow variability in retinal capillaries in human eyes. Understanding the heterogeneity in capillary flow is an important first step before pathological flow states can be properly understood. These results show that flow within capillary vessels is not affected by vessel depths but significantly influenced by the upstream feeder distance as well as the downstream vessel junction exponents, but there remains much to be uncovered regarding healthy capillary flow.

摘要

毛细血管流动在血管之间是非均匀的,且随时间变化,其原因尚未被充分理解。个体血管的局部特性在这方面的解释能力有限。这项探索性研究调查了网络级属性(如血管深度、分支顺序和距供血小动脉的距离)与毛细血管流动的关系。使用 flood-illuminated 自适应光学视网膜成像,对 3 名健康年轻受试者进行了详细的网络连通性分析,并通过光相干断层扫描血管造影确定了血管的轴向深度。在所研究的 70 条血管中,有 41 条属于终末毛细血管型,即由动脉交汇处供血,由静脉交汇处引流。大约一半的血管交汇处以相对分支直径模型拟合,只有少数符合 Murray 定律。模型的一个关键参数(交汇指数)与下游血管的平均速度(r = -0.59,p = 0.015)和低谷速度(r = -0.67,p = 0.004)呈负相关。细胞流动的某些方面,如最小速度,与距上游供血小动脉的距离也呈中度相关(r = 0.46,p = 0.009)。总体而言,这项研究表明,毛细血管网络拓扑结构对人眼视网膜毛细血管的流动变异性有重要贡献。在正确理解病理性流动状态之前,了解毛细血管流动的异质性是一个重要的第一步。这些结果表明,毛细血管内的流动不受血管深度的影响,但受上游供体距离以及下游血管交汇指数的显著影响,但对于健康毛细血管的流动,仍有许多未解之谜。

https://cdn.ncbi.nlm.nih.gov/pmc/blobs/b393/10575526/2b2414c7424b/pone.0292962.g001.jpg

文献AI研究员

20分钟写一篇综述,助力文献阅读效率提升50倍

立即体验

用中文搜PubMed

大模型驱动的PubMed中文搜索引擎

马上搜索