Abstract #3331

K-Space Density Weighted Functional Magnetic Resonance Imaging

Mario Zeller¹, Andreas J. Bartsch²,³, Alexander Mller¹, Marcel Gutberlet⁴, Dietbert Hahn¹, Herbert Kstler¹

¹Institute of Radiology, University of Wrzburg, Wrzburg, Germany; ²Department of Neuroradiology, University of Heidelberg, Heidelberg, Germany; ³FMRIB Centre, Oxford University, Oxford, United Kingdom; ⁴Institute for Interventional and Diagnostic Radiology, Hannover Medical School, Hannover, Germany

Echo planar images of conventional Cartesian fMRI are often spatially smoothed by a Gaussian filter prior to statistical analysis. K-space density weighting, on the other hand, allows to already record the data with a Gaussian shaped point spread function. This is achieved by sampling the k-space with a non-Cartesian trajectory. Such density weighting can, at the same time, be optimized for SNR efficiency by applying a matched filter. In this study, fMRI finger-tapping experiments were recorded with both approaches. Density weighting demonstrates significantly increased sensorimotor activations compared to conventional Cartesian imaging. Potential benefits of density weighted fMRI are discussed.