Iso-1.25mm Whole-cerebrum pCASL at 7T for Mapping Depth-dependent Cortical Gray Matter and Tract-specific White Matter Cerebral Blood Flow

Motivation: Mapping CBF in the whole cerebrum extent at a microvascular level at 7T has been hampered by SNR, susceptibility artifacts, BOLD effect, and field inhomogeneity. Goal(s): We aim to achieve an isotropic 1.25 whole cerebrum pCASL imaging. Approach: We developed a pCASL sequence which incorporates recent optimizations of labeling and background suppression and a 3D TFL readout. Poisson-disc undersampling and compressed sensing were used to improve image quality. Results: CBF mapping with high SNR and resolution was achieved, revealing depth-dependent CBF and an inverse relationship between tract-specific CBF and fractional anisotropy. Impact: The proposed pCASL imaging technique will impact neuroscientists by enabling fine-grained mapping of CBF at microvascular level in cortical gray matter and white matter at 7T.