Motivation: Spiral Diffusion MRI (dMRI) is limited by non-linear spatio-temporal field imperfections from eddy-currents, resulting in heavy blurring at high b-value and/or high resolution. NMR field probes accurately measure these imperfections, but require additional hardware, complexity, and cost. Goal(s): Characterize and correct diffusion gradient induced field imperfections in a PGSE spiral-dMRI sequence. Approach: Develop a rapid k-t calibration scan based on the FESTiVE algorithm to accurately map spatiotemporal eddy-currents from diffusion encoding in <10 seconds, and demonstrate effectiveness in spiral-dMRI reconstruction. Results: Estimated spatiotemporal eddy-current fields from D-FESTiVE are in strong agreement with gold-standard field-probe estimates (<5% difference), resulting in nearly indistinguishable reconstructions. Impact: We propose an alternative to field probes for eddy-current characterization in dMRI executable as a rapid pre-scan calibration. This will enable enhanced image reconstruction at high b-value without external hardware, enabling high-resolution fast imaging of brain connectivity and microstructure.
Shah et al. (Tue,) studied this question.