Linking Structure and Function: Image-Based Virtual Populations of the Retinal Vasculature DOI Creative Commons
Rémi J. Hernandez, Savita Madhusudhan, Yalin Zheng

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: Dec. 5, 2023

Abstract Purpose This study explores the relationship between microvascular parameters as delineated by optical coherence tomography angiography (OCTA) and retinal perfusion. We introduce a versatile framework to examine interplay vasculature structure function, generating virtual vasculatures from central vessels macular capillaries. Alongside this, we develop haemodynamics model which tests associations vascular morphology Methods The generation of is based on distribution four clinical pertaining dimension blood pressure vessels, constructive constrained optimisation Voronoi diagram. Arterial venous trees are generated in temporal retina connected through three layers capillaries at different depths macula. correlations total flow fraction derived Spearman rank coefficients uncertainty input quantified. Results A cohort 200 healthy were generated. Mean standard deviation for ratio 19.15 ± 7.34 μL / min 4.52 1.19 %. Retinal was correlated with vessel area density, diameter index, fractal calibre index. not any morphological metrics. Conclusions proposed able reproduce networks macula that morphologically functionally similar real vasculature. provides quantitative insights into how perfusion can be affected changes OCTA.

Language: Английский

Advancing treatment of retinal disease through in silico trials DOI Creative Commons
Rémi J. Hernandez, Paul Roberts, Wahbi K. El‐Bouri

et al.

Progress in Biomedical Engineering, Journal Year: 2023, Volume and Issue: 5(2), P. 022002 - 022002

Published: March 29, 2023

Abstract Treating retinal diseases to prevent sight loss is an increasingly important challenge. Thanks the configuration of eye, retina can be examined relatively easily in situ . Owing recent technological development scanning devices, much progress has been made understanding structure and characterising biomarkers. However, treatment options remain limited are often low efficiency efficacy. In years, concept silico clinical trials (ISCTs) adopted by many pharmaceutical companies optimise accelerate therapeutics. ISCTs rely on use mathematical models based physical biochemical mechanisms underpinning a biological system. With appropriate simplifications assumptions, one generate computer simulations various regimens, new therapeutic molecules, delivery strategies so forth, rapidly at fraction cost required for equivalent experiments. Such have potential not only hasten therapies but also existing this paper, we review state-of-the-art mathematicians, biomedical scientists clinicians, highlighting challenges developing ISCTs. Throughout highlight key findings from about physiology health disease. We describe main building blocks identify diseases.

Language: Английский

Citations

5
Bioinspired In Vitro Brain Vasculature Model for Nanomedicine Testing Based on Decellularized Spinach Leaves DOI

Aleksandra L. Predeina,

Artur Y. Prilepskii, V. de Zea Bermudez

et al.

Nano Letters, Journal Year: 2021, Volume and Issue: 21(23), P. 9853 - 9861

Published: Nov. 22, 2021

Animal testing is often criticized due to ethical issues and complicated translation of the results obtained clinical stage drug development. Existing alternative models for nanopharmaceutical still have many limitations do not significantly decrease number animals used. We propose a simple, bioinspired in vitro model based on decellularized spinach leaf's vasculature. This system similar human arterioles capillaries terms diameter (300–10 μm) branching. The has proven its suitability access maneuverability magnetic nanoparticles, particularly those composed Fe3O4. Moreover, thrombosis been recreated model's tested compared effects both single-chain urokinase plasminogen activator (scuPA) magnetically controlled nanocomposite prepared by heparin-mediated cross-linking scuPA with Fe3O4 nanoparticles. Compositions were static flow conditions.

Language: Английский

Citations

11
Linking Vascular Structure and Function: Image-Based Virtual Populations of the Retina DOI Creative Commons
Rémi J. Hernandez, Savita Madhusudhan, Yalin Zheng

et al.

Investigative Ophthalmology & Visual Science, Journal Year: 2024, Volume and Issue: 65(4), P. 40 - 40

Published: April 29, 2024

This study explored the relationship among microvascular parameters as delineated by optical coherence tomography angiography (OCTA) and retinal perfusion. Here, we introduce a versatile framework to examine interplay between vascular structure function generating virtual vasculatures from central vessels macular capillaries. Also, have developed hemodynamics model that evaluates associations morphology

Language: Английский

Citations

1
Biophysical modeling: An approach for understanding the physiological fingerprint of the BOLD fMRI signal DOI
Mario Gilberto Báez‐Yáñez,

Natalia Petridou

Elsevier eBooks, Journal Year: 2024, Volume and Issue: unknown, P. 119 - 157

Published: Jan. 1, 2024

Language: Английский

Citations

0
Mathematical Models of the Cerebral Microcirculation in Health and Pathophysiology DOI
Stephen J. Payne

SEMA SIMAI Springer series, Journal Year: 2024, Volume and Issue: unknown, P. 1 - 21

Published: Jan. 1, 2024

Language: Английский

Citations

0
Iatrogenic emboli during mechanical thrombectomy for acute ischemic stroke: comparison between stent retriever technique and contact aspiration—a retrospective case-control study DOI
Samuel Mouyal, Benjamin Granger, Kévin Janot

et al.

Journal of NeuroInterventional Surgery, Journal Year: 2024, Volume and Issue: unknown, P. jnis - 022206

Published: Nov. 2, 2024

Mechanical thrombectomy (MT) is an effective treatment for acute ischemic stroke from large vessel occlusion (LVO). While embolization to a new territory (ENT) after MT well-documented, data on in the same distal (EDT) are limited. Achieving modified Treatment In Cerebral Infarction (mTICI) 3 reperfusion presents significant clinical benefits over mTICI 2b/2c, necessitating strategies reduce both ENT and EDT. Previous studies suggest higher rates of EDTs with contact aspiration compared stentrievers. However, comprehensive comparison practice scarce. This study compares overall clot emboli (OCE) between these strategies.

Language: Английский

Citations

0
Quantification of hypoxic regions distant from occlusions in cerebral penetrating arteriole trees DOI Creative Commons
Yidan Xue, Theodosia Georgakopoulou, Anne‐Eva van der Wijk

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2022, Volume and Issue: unknown

Published: May 6, 2022

Abstract The microvasculature plays a key role in oxygen transport the mammalian brain. Despite close coupling between cerebral vascular geometry and local demand, recent experiments have reported that microvascular occlusions can lead to unexpected distant tissue hypoxia infarction. To better understand spatial correlation hypoxic regions occlusion sites, we used both vivo silico simulations investigate effects of penetrating arteriole trees on hypoxia. In rat model microembolisation, 25 µm microspheres were injected through carotid artery occlude arterioles. representative models human cortical columns, arterioles occluded by simulating same size was simulated using Green’s function method. locations segmented, two novel distance analyses implemented study their correlation. found be present simulations, mainly due hypoperfusion region downstream site. Furthermore, reasonable agreement for sites is shown which indicates good applicability understanding response blood flow microemboli. Author summary brain depends continuous supply bloodstream inside microvasculature. Occlusions network will disturb delivery result tissues infarction cognitive dysfunction. aid formation caused micro-occlusions trees, use rodent networks correlations locations. Our results suggest form distally from site, agrees with previous observations These are primarily lack occlusion. Moreover, relationship microemboli tissue.

Language: Английский

Citations

1
MRI-based computational model generation for cerebral perfusion simulations in health and ischaemic stroke DOI Creative Commons
Tamás Józsa, Jan Petr, Frederik Barkhof

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2022, Volume and Issue: unknown

Published: Sept. 8, 2022

Abstract Cerebral perfusion models were found to be promising research tools predict the impact of acute ischaemic stroke and related treatments on cerebral blood flow (CBF) linked patients’ functional outcome. To provide insights relevant clinical trials, simulations need become suitable for group-level investigations, but computational studies date have been limited a few patient-specific cases. This study set out overcome issues automated parameter inference, that restrict sample size simulations, by integrating neuroimaging data. Seventy-five brain generated using measurements from cohort 75 healthy elderly individuals model resting-state CBF distributions. Computational geometries adjusted reference subjects’ T1-weighted MRI. Haemodynamic parameters determined corresponding arterial spin labelling Thereafter, conducted 150 cases simulating an occlusion cessation in left right middle arteries. The anatomical (geometrical) fitness was evaluated comparing simulated grey white matter (GM WM) volumes subjects. Statistically significant, strong positive correlations both (GM: Pearson’s r 0.74, P -value< 0.001; WM: 0.84, 0.001). tuning verified total volumetric rate subjects resulting 0.89, 0.001. In cases, infarct volume perfusion-based proxy 197±25 ml. results showed excellent agreement with haemodynamic literature data T1-weighted, T2-weighted, phase-contrast MRI scenarios Simulation represented solely worst-case large infarcts because compensatory mechanisms, e.g. collaterals, neglected. established generation framework provides foundation population-level silico trials which could assist medical device drug development.

Language: Английский

Citations

1
Perfusion estimation using MRI-based measurements and a porous media flow model DOI Creative Commons
Rolf J. Lorentzen, Geir Nævdal,

Ove Sævareid

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: April 28, 2023

Abstract The measurement of perfusion and filtration blood in biological tissue give rise to important clinical parameters used diagnosis, follow-up, therapy. In this paper we address techniques for analysis using processed contrast agent concentration data from dynamic MRI acquisitions. New methodology is evaluated verified synthetic generated on a geometry. Author summary Accurate knowledge crucial proper diagnostics treatment several medical disorders. Traditional methods based imaging are fast, but usually lack precision robustness. paper, develop better diagnosis strategies malignant tumors stroke where may be altered. our work, mathematical models estimating calibrated magnetic resonance (MRI) data, more accurate representations provided. This step towards minimal invasive individually tailored treatment. We demonstrate the with twin-experiment different complexity generating parameters. Both description how fluids flows porous medium, data-generating model uses higher resolution network representation vessels than model. calibration unknown done statistical framework, choice motivated by applications sub-surface reservoir characterization.

Language: Английский

Citations

0
Perfusion estimation using synthetic MRI-based measurements and a porous media flow model DOI Creative Commons
Rolf J. Lorentzen, Geir Nævdal,

Ove Sævareid

et al.

PLoS Computational Biology, Journal Year: 2023, Volume and Issue: 19(10), P. e1011127 - e1011127

Published: Oct. 2, 2023

The measurement of perfusion and filtration blood in biological tissue give rise to important clinical parameters used diagnosis, follow-up, therapy. In this paper, we address techniques for analysis using processed contrast agent concentration data from dynamic MRI acquisitions. A new methodology is evaluated verified synthetic generated on a geometry.

Language: Английский

Citations

0