Fat quantification using a phase error-corrected cartesian acquisition with spiral profile ordering (CASPR)

Motivation: Complex-based fat quantification techniques are sensitive to phase errors and motion, particularly in free-breathing acquisitions. Goal(s): To develop a phase-corrected time-interleaved multi-echo gradient echo (TIMGRE) technique employing a cartesian spiral profile ordering (CASPR) for robust fat quantification, while exploring the flexibility and self-gating capabilities of the trajectory. Approach: A framework was developed for correcting eddy current and concomitant gradient phase errors in a TIMGRE-CASPR acquisition at 3T. Validation was conducted in a large-FOV water phantom, a water-fat phantom and in vivo. Results: Phase correction for a monopolar time-interleaved six-echo CASPR enables quantitative water-fat mapping inside motion-affected areas such as the liver. Impact: Prior studies have established the CASPR trajectory as an efficient and easily customizable trajectory with self-gating motion capabilities. This work is the first to use the CASPR trajectory for fat quantification, while simultaneously addressing phase error effects.