Molly Gallogly Bright1,2, Daniel P. Bulte2,
Peter Jezzard2, Jeff H. Duyn1
1Advanced MRI Section,
LFMI, NINDS, National Institutes of Health, Bethesda, MD, United States; 2FMRIB
Centre, University of Oxford, Oxford, Oxfordshire, United Kingdom
Cerebrovascular reactivity to changes in arterial gas tensions offers clinical insight into vessel health and compliance. The BOLD response to a new respiratory challenge of Cued Deep Breathing enables accessible mapping of reactivity and response dynamics. At 7 Tesla, the enhanced magnitude of the BOLD response to this challenge enables voxelwise fitting for % signal change, time-to-peak (TTP), onset time, and full-width-half-minimum of the response throughout the brain. TTP is a robust surrogate for the other, more subtle temporal parameters, and results further establish, in individual subjects, the regional heterogeneity observed previously across a healthy population at 3 Tesla.