2D T1, T2, T2* and PDFF mapping in the kidney with rosette MRF using Hermitian low-rank and dictionary-patch based regularization

Motivation: Subjective qualitative T2-weighted, T1-weighted (with and without contrast) and fat suppressed images are currently used to characterize renal masses. Characterization could be improved and standardized by using objective, generalizable, quantiative criteria. Goal(s): In this work, 2D single-breathhold, high-resolution T1/T2/T2*/PDFF mapping rosette MRF is deployed for kidney tissue characterization. Approach: A novel MRF reconstruction is introduced to enable reduced MRF data collection time, incorporating separate low-rank models along the TE and TR domains, Hermitian symmetry via virtual coils, and a dictionary-patch based regularization. Results: In vivo results in healthy subjects demonstrate 2D 1x1x5 mm3 T1/T2/T2*/PDFF MRF kidney mapping in a single breath-hold. Impact: Simultaneous mapping of T1/T2/T2*/PDFF in the kidney in a single high-resolution breath-hold scan via the proposed MRF approach is feasible. This technique could bolster traditional pre-/post- contrast renal mass protocols with objective characterization methods.