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Abstract #2154

BOLD, CBF, and CBV FMRI Measurements in Chronic Stroke Patients Reveal Details of Altered Neurovascular Coupling

Manus Donahue1, 2, Charlotte Stagg2, Jacinta O'Shea2, Peter Jezzard2, Leif Ostergaard3, Bradley MacIntosh, 24, Heidi Johansen-Berg2, Jakob Blicher3

1Vanderbilt University, Nashville, TN, United States; 2FMRIB Centre, Oxford University, Oxford, Oxfordshire, United Kingdom; 3Center of Functionally Integrative Neuroscience, Aarhus University, Aarhus, Denmark; 4Medical Biophysics, University of Toronto, Toronto, Ontario, Canada

The aim of this work is to apply a multi-modal, noninvasive fMRI approach to better quantify hemodynamic compensation mechanisms during stroke recovery (n=22). Despite robust BOLD, CBF-weighted and CBV-weighted reactivity changes in healthy subjects, in stroke patients with motor impairment, BOLD-fMRI yielded no significant (P>0.05) average changes, despite significant (P<0.01) changes in CBF and CBV. Therefore in chronic stroke, neuronal activity can lead to measurable changes in CBF and CBV in expected cortical areas despite an absent BOLD-fMRI response. Thus, multi-modal fMRI may be better suited than BOLD-fMRI for interrogating cortical reorganization under circumstance of impaired neurovascular coupling.

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Keywords

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