Modelling the impact of clot fragmentation on the microcirculation after thrombectomy

El-Bouri, Wahbi K ORCID: 0000-0002-2732-5927, MacGowan, Andrew, Jozsa, Tamas I, Gounis, Matthew J and Payne, Stephen J (2021) Modelling the impact of clot fragmentation on the microcirculation after thrombectomy. PLOS COMPUTATIONAL BIOLOGY, 17 (3). e1008515-.

This is the latest version of this item.

	Text journal.pcbi.1008515.pdf - Published version Download (8MB) \| Preview
	Text Modelling the impact of clot fragmentation on the microcirculation after thrombectomy.pdf - Published Version Download (3MB) \| Preview

Official URL: http://dx.doi.org/10.1371/journal.pcbi.1008515

Abstract

Many ischaemic stroke patients who have a mechanical removal of their clot (thrombectomy) do not get reperfusion of tissue despite the thrombus being removed. One hypothesis for this 'no-reperfusion' phenomenon is micro-emboli fragmenting off the large clot during thrombectomy and occluding smaller blood vessels downstream of the clot location. This is impossible to observe in-vivo and so we here develop an in-silico model based on in-vitro experiments to model the effect of micro-emboli on brain tissue. Through in-vitro experiments we obtain, under a variety of clot consistencies and thrombectomy techniques, micro-emboli distributions post-thrombectomy. Blood flow through the microcirculation is modelled for statistically accurate voxels of brain microvasculature including penetrating arterioles and capillary beds. A novel micro-emboli algorithm, informed by the experimental data, is used to simulate the impact of micro-emboli successively entering the penetrating arterioles and the capillary bed. Scaled-up blood flow parameters-permeability and coupling coefficients-are calculated under various conditions. We find that capillary beds are more susceptible to occlusions than the penetrating arterioles with a 4x greater drop in permeability per volume of vessel occluded. Individual microvascular geometries determine robustness to micro-emboli. Hard clot fragmentation leads to larger micro-emboli and larger drops in blood flow for a given number of micro-emboli. Thrombectomy technique has a large impact on clot fragmentation and hence occlusions in the microvasculature. As such, in-silico modelling of mechanical thrombectomy predicts that clot specific factors, interventional technique, and microvascular geometry strongly influence reperfusion of the brain. Micro-emboli are likely contributory to the phenomenon of no-reperfusion following successful removal of a major clot.

Item Type:	Article
Uncontrolled Keywords:	Microcirculation, Humans, Brain Ischemia, Thrombosis, Treatment Outcome, Thrombectomy
Divisions:	Faculty of Health and Life Sciences Faculty of Health and Life Sciences > Institute of Life Courses and Medical Sciences
Depositing User:	Symplectic Admin
Date Deposited:	10 May 2021 08:01
Last Modified:	18 Jan 2023 22:48
DOI:	10.1371/journal.pcbi.1008515
Related URLs:	Author Publisher
URI:	https://livrepository.liverpool.ac.uk/id/eprint/3122118