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MRI Mapping of Cerebrovascular Reactivity via Gas Inhalation Challenges
Published on: December 17, 2014
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Multi-echo BOLD fMRI improves cerebrovascular reactivity estimates in stroke.
Rebecca G Clements1,2, Fatemeh Geranmayeh3,4, Niamh V Parkinson3,4
1Department of Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
Biorxiv : the Preprint Server for Biology
|February 12, 2026
Summary
Multi-echo fMRI techniques significantly improve cerebrovascular reactivity (CVR) estimation in stroke patients. These methods enhance CVR quality, especially in low signal-to-noise data, aiding stroke research.
Area of Science:
- Neuroimaging
- Vascular Neurology
- Biomedical Engineering
Background:
- Cerebrovascular reactivity (CVR) assesses cerebrovascular health but is sensitive to noise in clinical populations.
- Head motion and signal noise degrade CVR quality, limiting its clinical utility, especially in stroke patients.
Purpose of the Study:
- To evaluate multi-echo fMRI techniques for enhancing CVR quality in participants with stroke.
- To compare multi-echo optimal combination (ME-OC) and multi-echo independent component analysis (ME-ICA) against single-echo fMRI.
Main Methods:
- Analysis of a breath-hold fMRI dataset from stroke participants using ME-OC and ME-ICA.
- Evaluation of a separate resting-state fMRI dataset from stroke participants.
- Assessment of CVR quality metrics and motion-related signal changes.
Main Results:
- ME-OC improved CVR quality and reduced negative CVR values in normal-appearing gray and white matter in the breath-hold dataset.
- ME-ICA reduced motion-BOLD signal dependence but did not initially improve CVR quality.
- In the resting-state dataset, ME-OC showed consistent benefits, while ME-ICA significantly improved CVR quality over ME-OC.
Conclusions:
- Multi-echo fMRI techniques, particularly ME-OC and ME-ICA, can substantially improve CVR estimation in clinical populations like stroke patients.
- These advanced fMRI methods enhance CVR analysis feasibility in low signal-to-noise conditions, improving visualization of stroke-related CVR deficits.
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