The severity of microstrokes depends on local vascular topology and baseline perfusion
Abstract
Cortical microinfarcts are linked to pathologies like cerebral amyloid angiopathy and dementia. Despite their relevance for disease progression, microinfarcts often remain undetected and the smallest scale of blood flow disturbance has not yet been identified. We employed blood flow simulations in realistic microvascular networks from the mouse cortex to quantify the impact of single capillary occlusions. Our simulations reveal that the severity of a microstroke is strongly affected by the local vascular topology and the baseline flow rate in the occluded capillary. The largest changes in perfusion are observed in capillaries with two in- and two outflows. This specific topological configuration only occurs with a frequency of 8%. The majority of capillaries has one in- and one outflow and is likely designed to efficiently supply oxygen and nutrients. Taken together, microstrokes bear potential to induce a cascade of local disturbances in the surrounding tissue, which might accumulate and impair energy supply locally.
Data availability
We provide all time-averaged simulation results as well as relevant analysis scripts.
Article and author information
Author details
Funding
University of Zurich - Forschungskredit (FK-19-045)
- Franca Schmid
European Union's Horizon 2020 Framework Program for Research and Innovation (Specific Grant Agreement No. 720270 (Human Brain Project SGA1))
- Franca Schmid
European Union's Horizon 2020 Framework Program for Research and Innovation (Specific Grant Agreement No. 785907 (Human Brain Project SGA2))
- Franca Schmid
Swiss National Science Foundation (310030_182703)
- Bruno Weber
Swiss National Science Foundation (SNF CR23I2_166707)
- Bruno Weber
Swiss National Science Foundation (SNF CR23I2_166707)
- Patrick Jenny
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Mark T Nelson, University of Vermont, United States
Version history
- Received: June 19, 2020
- Accepted: May 17, 2021
- Accepted Manuscript published: May 18, 2021 (version 1)
- Version of Record published: September 6, 2021 (version 2)
Copyright
© 2021, Schmid et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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