Correction of Eddy Current Induced Phase Variations between Imaging and Navigator Echoes in High Angular Resolution Diffusion Imaging

Motivation: The time-varying eddy current caused by diffusion gradient can induce additional phase difference between imaging and navigator echoes. These inaccurate measurements may cause residual artifacts in the subsequently reconstructed data. Goal(s): This study aims to verify the presence of the eddy-current-induced phase differences in navigator echoes and the phase correction can improve reconstruction performance on in-vivo DTI and HARDI. Approach: We proposed a procedure to calibrate eddy-current-induced phase difference from a phantom and considered the additional phase difference when using k-d SVD method for reconstruction. Results: The robust reconstruction performance can be achieved by using phase-corrected navigator data to recover highly-undersampled data. Impact: This study demonstrates that the eddy-current-induced phase differences between imaging and navigator echoes can be calibrated in advance, and then corrected during the k-d SVD reconstruction method to enable highly-accelerated multi-shot high angular resolution diffusion imaging (HARDI).