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Updated: Feb 13, 2026

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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
PubMed

Insights

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.

Keywords:
breath-hold fMRIcerebrovascular reactivitymulti-echo fMRIresting-state fMRIstroke

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