CT perfusion in acute ischaemic stroke within 24 hours of onset

Biswas, Viveka (2024) CT perfusion in acute ischaemic stroke within 24 hours of onset. PhD thesis, University of Glasgow.

Abstract

This work, presented for examination, addresses how advanced imaging in acute stroke may be used across time windows, to identify the population who will benefit the most from reperfusion therapy at a time when resources are limited.

The time windows for reperfusion therapy have been extended (from 4.5 and 6 hours) to 9 and 24 hours for thrombolysis and endovascular therapy respectively. This extension depends on advanced imaging of penumbra and collateral circulation. However, uncertainties exist surrounding the proportion of patients with prolonged penumbral survival tissue, failure to recruit leptomeningeal collaterals and validation of current thresholds for prediction of tissue fate in late time windows.

We conducted a prospective, single-centre, observational study. Our primary objective was to identify the proportion of patients with salvageable brain tissue, at different time windows up to 24 hours after onset of acute ischaemic stroke. We also assessed collateral circulation (using both perfusion and angiographic imaging), the biological factors which may predict its demise and the time thresholds for ischaemia. We analysed imaging using three commonly used commercial software which process scans using Artificial Intelligence and found systematic differences which may influence treatment decisions.

Improved understanding of the mechanisms underpinning collateral flow, particularly the relevance of hyperglycaemia, is important in identifying a group of patients in whom very early intervention may sustain viable tissue for longer, opening the door for therapeutic interventions such as delayed revascularisation in a wider clinical group.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Additional Information: Supported by funding from the Chief Scientist Office, NHS Research Scotland and the Neurosciences Foundation.
• Subjects: B Philosophy. Psychology. Religion > BF Psychology; R Medicine > RC Internal medicine > RC0321 Neuroscience. Biological psychiatry. Neuropsychiatry
• Colleges/Schools: College of Medical Veterinary and Life Sciences > School of Psychology & Neuroscience
• Funder's Name: Office of the Chief Scientific Adviser (CSO), NHS Research Scotland, Neurosciences Foundation
• Supervisor's Name: Muir, Professor Keith
• Date of Award: 2024
• Depositing User: Theses Team
• Unique ID: glathesis:2024-84785
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 06 Jan 2025 16:16
• Last Modified: 06 Jan 2025 16:17
• Thesis DOI: 10.5525/gla.thesis.84785
• URI: https://theses.gla.ac.uk/id/eprint/84785