Fast, motion-robust CEST imaging with inherent B0 correction using rosette trajectories

Motivation: CEST-MRI typically requires a long scan time and an additional B0 map scan for inhomogeneity correction. Goal(s): To implement a rosette readout for fast CEST imaging with improved robustness to bulk-motion and inherent correction of B0 inhomogeneity. Approach: Rosette trajectories which sample more densely near the k-space center provided faster and more motion-robust CEST imaging than Cartesian trajectories. B0 inhomogeneities were estimated using the phase difference between two images from two halves of the rosette lobe and corrected subsequently. Results: Rosette trajectories significantly reduced the CEST imaging time. No extra scans were needed for B0 correction due to the inherent B0 mapping capability. Impact: Fast, motion-robust, and inherent B0-corrected CEST imaging with rosette trajectories can help improve patient comfort and compliance. The work is expected to significantly accelerate the translation of CEST-MRI into a robust clinically viable approach.