Vishaal Sumra1,2, Tobias C Wood3, and Sofia Chavez1,2
1Institute of Medical Science, University of Toronto, Toronto, ON, Canada, 2Brain Health Imaging Centre - MRI, Centre for Addiction and Mental Health, Toronto, ON, Canada, 3Department of Neuroimaging, King's College London, London, United Kingdom
1Institute of Medical Science, University of Toronto, Toronto, ON, Canada, 2Brain Health Imaging Centre - MRI, Centre for Addiction and Mental Health, Toronto, ON, Canada, 3Department of Neuroimaging, King's College London, London, United Kingdom
Acquisition of complex multi-echo SPGR data for 2 flip angles allows for the generation of multi-parametric maps, including qT1 and QSM in the same space, through optimal processing of complex data.
Figure 4. SWI, B0 and QSM processing schematic. Echo 1 phase was removed from echo 2-6 complex data in order to facilitate phase alignment across flip angles, prior to complex averaging. Complex phase difference data for both flip angles (α = 3° & 24°) were averaged for echoes 2-6. Echo 6 data alone was unwrapped, filtered and processed to create SWI, and echoes 2-6 data were processed to generate QSM. For B0 processing, all data was resampled to 2mm isotropic prior to phase rotation and averaging, then phase unwrapped and fit to a linear function (Δθ vs ΔTE) to map B0.
Figure 1. Acquisition of multi-echo SPGR complex data allows for the generation of multi-parametric maps.
