B0 mapping using rewinding trajectories (BMART).
Ontology highlight
ABSTRACT: Purpose
To create a B0 map and correct for off-resonance with minimal scan time increase for two-dimensional (2D) or 3D non-Cartesian acquisitions.Methods
Rewinding trajectories that bring the zeroth gradient moment to zero every repetition time (TR) were used to estimate the off-resonance with a center-out 3D cones trajectory, which required an increase in the minimum TR by 5%. The off-resonance estimation and correction was implemented using an algorithm based on binning and object-domain phase correction. B0 maps using BMART (B0 mapping using rewinding trajectories) were compared to maps obtained using separate scans with multiple echo time (TE) in a phantom and human brain.Results
Excellent agreement between BMART and the multiple-TE method were observed, and images corrected with BMART were deblurred.Conclusion
BMART can correct for off-resonance without requiring an additional scan, and can be easily applied to center-out or projection trajectories (2D or 3D). Magn Reson Med 78:664-669, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
SUBMITTER: Baron CA
PROVIDER: S-EPMC5325829 | biostudies-literature | 2017 Aug
REPOSITORIES: biostudies-literature
Publications
B<sub>0</sub> mapping using rewinding trajectories (BMART).
Baron Corey A CA Nishimura Dwight G DG
Magnetic resonance in medicine 20160824 2
<h4>Purpose</h4>To create a B<sub>0</sub> map and correct for off-resonance with minimal scan time increase for two-dimensional (2D) or 3D non-Cartesian acquisitions.<h4>Methods</h4>Rewinding trajectories that bring the zeroth gradient moment to zero every repetition time (TR) were used to estimate the off-resonance with a center-out 3D cones trajectory, which required an increase in the minimum TR by 5%. The off-resonance estimation and correction was implemented using an algorithm based on bin ...[more]
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