01 Mar 21. Featured Paper

Cerebrovascular reactivity measurement using magnetic resonance imaging: a systematic review

Link to paper on Frontiers in Physiology

Authors

Emilie Sleight, Michael S. Stringer, Ian Marshall, Joanna M. Wardlaw, & Michael J. Thrippleton

Abstract

Cerebrovascular reactivity (CVR) magnetic resonance imaging (MRI) probes cerebral haemodynamic changes in response to a vasodilatory stimulus.

CVR closely relates to the health of the vasculature & is therefore a key parameter for studying cerebrovascular diseases such as stroke, small vessel disease & dementias.

MRI allows in vivo measurement of CVR but several different methods have been presented in the literature, differing in pulse sequence, hardware requirements, stimulus & image processing technique.

We systematically reviewed publications measuring CVR using MRI up to June 2020, identifying 235 relevant papers.

We summarised the acquisition methods, experimental parameters, hardware & CVR quantification approaches used, clinical populations investigated, & corresponding summary CVR measures.

CVR was investigated in many pathologies such as steno-occlusive diseases, dementia & small vessel disease & is generally lower in patients than in healthy controls.

Blood oxygen level dependent (BOLD) acquisitions with fixed inspired CO₂ gas or end-tidal CO₂ forcing stimulus are the most commonly used methods.

General linear modelling of the MRI signal with end-tidal CO₂ as the regressor is the most frequently used method to compute CVR.

Our survey of CVR measurement approaches & applications will help researchers to identify good practice & provide objective information to inform the development of future consensus recommendations.

Keywords

• Arterial spin labelling MRI
• Blood oxygen-level dependent
• Cerebrovascular reactivity
• Hypercapnia (CO(2)) inhalation
• Magnetic resonance imaging
• Systematic review