David
Z. Balla1, 2, Rosa M. Sanchez-Panchuelo2,
Sam Wharton2, Gisela E. Hagberg3, Klaus Scheffler1,
4, Sue T. Francis2, Richard W. Bowtell2
1High-Field MR Centre, Max Planck Institute for Biological Cybernetics, Tuebingen, Germany; 2Sir Peter Mansfield Magnetic Resonance Centre, University of Nottingham, Nottingham, United Kingdom; 3Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, Tuebingen, Germany; 4Department of Neuroimaging and MR-Physics, University of Tuebingen, Tuebingen, Germany
Quantitative susceptibility mapping (QSM) was performed on fMRI time-series to reconstruct maps with activation induced local susceptibility changes. A multi-step image processing algorithm was developed for filtering out unwanted temporal and spatial signal variations. The method was validated on GE-EPI BOLD-fMRI datasets acquired at 7T with 1mm isotropic resolution during the application of visual, motor and somatosensory activation paradigms. Series of high-quality phase and susceptibility maps with minimal temporal noise were reconstructed, which resulted in activation maps corresponding to estimations from the modulus data. Functional QSM (fQSM) allows for quantification of the BOLD-effect for any time-series with phase information.