Bernard Siow1, David W. Carmichael2,3,
Johannes Riegler4, Daniel Alexander1, Mark Lythgoe4,
Roger Ordidge3
1Centre for Medical Image Computing,
University College London, London, United Kingdom; 2Institute of
Neurology, University College London, United Kingdom; 3Department
of Medical Physics and Bioengineering, University College London, United
Kingdom; 4Centre for Advanced Biomedical Imaging, University
College London, United Kingdom
The
Sub-pixel Enhancement of Nonuniform Tissue (SPENT) sequence applies a 2pi
phase dispersion across each voxel: the net phase of spins in magnetically
homogeneous voxels would be equal to zero and thus no signal would be
generated. If there are sub-pixel inhomogeneities, then the net phase of
spins in a voxel is not zero and thus signal is seen. In this study, human
mononuclear cells labelled with micron-sized iron oxide particles, which
creates sub-voxel perturbations in the field, are scanned with a spin-echo
SPENT sequence producing positive contrast images. SPENT provides directional
information, as well as the potential for quantification.