Open AccessCalibrated imaging reveals altered grey matter metabolism related to white matter microstructure and symptom severity in multiple sclerosis
Author(s) -
Hubbard Nicholas A.,
Turner Monroe P.,
Ouyang Minhui,
Himes Lyndahl,
Thomas Binu P.,
Hutchison Joanna L.,
Faghihahmadabadi Shawheen,
Davis Scott L.,
Strain Jeremy F.,
Spence Jeffrey,
Krawczyk Daniel C.,
Huang Hao,
Lu Hanzhang,
Hart John,
Frohman Teresa C.,
Frohman Elliot M.,
Okuda Darin T.,
Rypma Bart
Publication year - 2017
Publication title -
human brain mapping
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.005
H-Index - 191
eISSN - 1097-0193
pISSN - 1065-9471
DOI - 10.1002/hbm.23727
Subject(s) - white matter , grey matter , diffusion mri , neuroimaging , magnetic resonance imaging , multiple sclerosis , neuroscience , psychology , neurology , population , medicine , radiology , psychiatry , environmental health
Multiple sclerosis (MS) involves damage to white matter microstructures. This damage has been related to grey matter function as measured by standard, physiologically‐nonspecific neuroimaging indices (i.e., blood‐oxygen‐level dependent signal [BOLD]). Here, we used calibrated functional magnetic resonance imaging and diffusion tensor imaging to examine the extent to which specific, evoked grey matter physiological processes were associated with white matter diffusion in MS. Evoked changes in BOLD, cerebral blood flow (CBF), and oxygen metabolism (CMRO 2 ) were measured in visual cortex. Individual differences in the diffusion tensor measure, radial diffusivity, within occipital tracts were strongly associated with MS patients’ BOLD and CMRO 2 . However, these relationships were in opposite directions, complicating the interpretation of the relationship between BOLD and white matter microstructural damage in MS. CMRO 2 was strongly associated with individual differences in patients’ fatigue and neurological disability, suggesting that alterations to evoked oxygen metabolic processes may be taken as a marker for primary symptoms of MS. This work demonstrates the first application of calibrated and diffusion imaging together and details the first application of calibrated functional MRI in a neurological population. Results lend support for neuroenergetic hypotheses of MS pathophysiology and provide an initial demonstration of the utility of evoked oxygen metabolism signals for neurology research. Hum Brain Mapp 38:5375–5390, 2017 . © 2017 Wiley Periodicals, Inc.