Free-running 3D whole-heart T1 and T2 mapping and cine MRI using low-rank reconstruction

Abstract

Abstract
Purpose
To introduce non-rigid cardiac motion correction into a novel free-running framework for the simultaneous acquisition of 3D whole-heart myocardial T1 and T2 maps and cine images, enabling a 3-min scan.

Methods
Data were acquired using a free-running 3D golden-angle radial readout interleaved with inversion recovery and T2-preparation pulses. After correction for translational respiratory motion, non-rigid cardiac-motion-corrected reconstruction with dictionary-based low-rank compression and patch-based regularization enabled 3D whole-heart T1 and T2 mapping at any given cardiac phase as well as whole-heart cardiac cine imaging. The framework was validated and compared with established methods in 11 healthy subjects.

Results
Good quality 3D T1 and T2 maps and cine images were reconstructed for all subjects. Septal T1 values using the proposed approach ( 1200 +- 50ms) were higher than those from a 2D MOLLI sequence ( 1063+-33ms), which is known to underestimate T1, while T2 values from the proposed approach (51+-4 ms) were in good agreement with those from a 2D GraSE sequence (51+-2 ms).

Conclusion
The proposed technique provides 3D T1 and T2 maps and cine images with isotropic spatial resolution in a single 3.3-min scan.