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Abstract #0845

Elimination of Non-Steady-State Blood Spins in Vascular-Space-Occupancy (VASO) FMRI

Jun Hua1, 2, Craig K. Jones1, 2, Qin Qin1, 2, Peter C.M. van Zijl1, 2

1Neurosection, Div. of MRI Research, Dept. of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States; 2F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, United States

We show that contaminations from the non-steady-state inflowing blood spins in Vascular-space-occupancy (VASO) fMRI can be eliminated by combining the previously proposed magnetization reset technique with motion-sensitized crushing gradients. The magnetization reset module is a spatially nonselective saturation applied immediately after readout. The crushing gradients can be implemented with bipolar gradients in a 2D sequence such as 2D gradient echo (GRE) echo-planar-imaging (EPI), or a motion-sensitized driven equilibrium (MSDE) spin preparation module immediately before a 3D sequence such as 3D fast GRE. When performing VASO fMRI of visual stimulation, the combined technique successfully suppressed the non-steady-state blood spins.

Keywords

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