First Application of a 3D Radial Trajectory for Free-Breathing ECG-Triggered Cardiac T1ρ Mapping at 1.5 T

Motivation: Most cardiac T1ρ mapping techniques collect data in 2D, while the few existing 3D methods use a Cartesian sampling trajectory. Goal(s): In this study, we report the first use of a 3D radial trajectory for whole-heart T1ρ mapping at 1.5 T. Approach: The proposed technique was validated in a phantom, tested in one volunteer, and compared to a 2D reference method. Results: Our results show that the T1ρ values obtained from our 3D technique are comparable to the 2D reference values for both phantom and volunteer. However, we observed an underestimation of the T1ρ values using the 3D method in the phantom. Impact: 3D radial free-breathing electrocardiogram-triggered cardiac T1ρ mapping at 1.5 T has the potential to serve as a contrast agent-free adjunct to late gadolinium enhancement imaging for the whole-heart motion-robust quantification of tissue properties such as myocardial fibrosis.