Skip to main content

Research Repository

Advanced Search

Field strength dependence of grey matter R2* on venous oxygenation

Croal, Paula L.; Driver, Ian D.; Francis, Susan T.; Gowland, Penny A.

Authors

Paula L. Croal

Ian D. Driver



Abstract

The relationship between venous blood oxygenation and change in transverse relaxation rate (ΔR2 *) plays a key role in calibrated BOLD fMRI. This relationship, defined by the parameter β, has previously been determined using theoretical simulations and experimental measures. However, these earlier studies have been confounded by the change in venous cerebral blood volume (CBV) in response to functional tasks. This study used a double-echo gradient echo EPI scheme in conjunction with a graded isocapnic hyperoxic sequence to assess quantitatively the relationship between the fractional venous blood oxygenation (1-Yv) and transverse relaxation rate of grey matter (ΔR2 * GM), without inducing a change in vCBV.

The results demonstrate that the relationship between ΔR2 * and fractional venous oxygenation at all magnet field strengths studied was adequately described by a linear relationship. The gradient of this relationship did not increase monotonically with field strength, which may be attributed to the relative contributions of intravascular and extravascular signals which will vary with both field strength and blood oxygenation.

Citation

Croal, P. L., Driver, I. D., Francis, S. T., & Gowland, P. A. (2017). Field strength dependence of grey matter R2* on venous oxygenation. NeuroImage, 146, 327-332. https://doi.org/10.1016/j.neuroimage.2016.10.004

Journal Article Type Article
Acceptance Date Oct 1, 2016
Online Publication Date Oct 5, 2016
Publication Date 2017-02
Deposit Date Oct 17, 2016
Publicly Available Date Oct 17, 2016
Journal NeuroImage
Print ISSN 1053-8119
Electronic ISSN 1095-9572
Publisher Elsevier
Peer Reviewed Peer Reviewed
Volume 146
Pages 327-332
DOI https://doi.org/10.1016/j.neuroimage.2016.10.004
Keywords calibrated BOLD; fMRI; R2⁎ quantification; oxygenation;
hyperoxia
Public URL https://nottingham-repository.worktribe.com/output/824592
Publisher URL http://www.sciencedirect.com/science/article/pii/S1053811916305523

Files

1-s2 0-S1053811916305523-main.pdf (1.5 Mb)
PDF

Copyright Statement
Copyright information regarding this work can be found at the following address: http://creativecommons.org/licenses/by/4.0





You might also like



Downloadable Citations