Lars Kasper1,2, S. Johanna Vannesj1,
Maximimilian Hberlin1, Christoph Barmet1, Klaas Enno
Stephan2,3, Klaas Paul Prssmann1
1University and ETH Zurich, Institute
for Biomedical Engineering, Zurich, Switzerland; 2Institute for
Empirical Research in Economics, University of Zurich, Laboratory for Social
and Neural Systems Research, Zurich, Switzerland; 3 Institute of
Neurology, University College London, Wellcome Trust Centre for Neuroimaging,
London, United Kingdom
Smoothing
MR-images is a common preprocessing step in areas like functional MRI to
improve signal as well as noise characteristics of the images and facilitate
inter-subject comparison. We present how an EPI-acquisition scheme (1.5 mm
resolution) whose density is specifically tailored to match an image
smoothing kernel improves the SNR of the finally smoothed images.
Furthermore, this shows the opportunity to assign differing spatial
properties to signal and noise contributions within an MR image. Because
these non-uniform trajectories differ from common MR gradient demands, we
relied on actually measured trajectories for our reconstructions, using an
NMR field monitoring setup.