Yuji Shen1, Ida Mengyi Pu2, Risto A. Kauppinen3
1School of Medicine, University of Birmingham, Birmingham, UK; 2Department of Computing, Goldsmiths, University of London, London, UK; 3Biomedical NMR Research Center, Dartmouth Medical School, Hanover, NH 03755, USA
MR signal measured by grey matter nulled (GMN) fMRI is affected by partial volume effects from CSF, complicating quantification of possible change in absolute CBV. We present an approach to estimate change in absolute CBV to brain activation by determining blood and CSF signals separately at voxel level. Two different TRs were used to acquire GMN fMRI data which were used for quantification of CBV. Increase in absolute CBV was found to be 16.7 5.8% in the visual cortex to checkerboard stimulation, which is significantly more than the increase in raw GMN fMRI signal by 7.0 1.9%.
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