Abstract #1645

Characterizing the BOLD Response to Transient Respiratory Challenges at 7 Tesla

Molly Gallogly Bright^1,2, 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.