Motion-informed free-breathing myocardial 3D T1rho mapping at 0.6T

Motivation: Myocardial T1rho mapping has shown promising results for myocardial injury characterization, but suffers from B1/B0-inhomogeneities. Reduced static field strengths offer improved homogeneity and accessibility, at the cost of SNR. Goal(s): To show the feasibility of free-breathing 3D T1rho mapping with motion-informed reconstruction at reduced field strengths. Approach: Free-breathing 3D T1rho imaging was performed on volunteers with a magnetization-prepared bSSFP sequence on a 0.6T scanner. Reconstruction was performed using motion-informed higher-order singular value decomposition reconstruction (MI-HOSVD), non-motion-compensated HOSVD and navigator-gated HOSVD. Results: High-quality T1rho maps were reconstructed using MI-HOSVD with improved image quality and reduced fitting errors when compared to the other reconstruction methods. Impact: MI-HOSVD reconstruction efficiently and effectively uses data from all breathing states, thereby improving free-breathing 3D T1rho mapping at 0.6T.