Magnetic Resonance Fingerprinting for Simultaneous T1, T2 and ADC Mapping at 0.55T using Convex-optimized Diffusion Prepared Waveforms

Motivation: Single breath-hold simultaneous T1, T2, and ADC MRF allows comprehensive tissue characterization in a single scan. However, this technique has not been demonstrated at 0.55T. Goal(s): Investigate the feasibility of T1, T2, and ADC MRF sequence for simultaneous T1, T2, and ADC mapping at 0.55T taking full advantage of the low-field scanner hardware. Approach: The proposed approach uses a bSSFP radial sequence with varying IR, T2-preparation, and optimized ADC-preparation pulses over 16 heartbeats. Experiments were performed on phantoms and compared with spin-echo references. Results: T1, T2, and ADC MRF at 0.55T was tested in a phantom, showing excellent agreement with reference values. Impact: Simultaneous quantification of T1, T2, and ADC is feasible with the proposed MRF sequence in a single breathold, allowing for a more comprehensive tissue characterization through co-registered multiparametric imaging at 0.55T with a low-performance gradient system.