A novel 3D free-breathing cardiac mapping technique achieved efficient joint myocardial T1 (1236 ± 59 ms) and T1ρ (50.2 ± 2.4 ms) mapping comparable to 2D breath-hold techniques.
A novel 3D free-breathing cardiac MRI framework enables efficient and simultaneous myocardial T1 and T1ρ mapping at 3T with comparable results to standard 2D breath-hold techniques.
PURPOSE: To develop a 3D free-breathing cardiac multi-parametric mapping framework that is robust to confounders of respiratory motion, fat, and B1+ inhomogeneities and validate it for joint myocardial T1 and T1ρ mapping at 3T. METHODS: An electrocardiogram-triggered sequence with dual-echo Dixon readout was developed, where nine cardiac cycles were repeatedly acquired with inversion recovery and T1ρ preparation pulses for T1 and T1ρ sensitization. A subject-specific respiratory motion model relating the 1D diaphragmatic navigator to the respiration-induced 3D translational motion of the heart was constructed followed by respiratory motion binning and intra-bin 3D translational and inter-bin non-rigid motion correction. Spin history B1+ inhomogeneities were corrected with optimized dual flip angle strategy. After water-fat separation, the water images were matched to the simulated dictionary for T1 and T1ρ quantification. Phantoms and 10 heathy subjects were imaged to validate the proposed technique. RESULTS: = 0.98) with the reference measurements in phantoms. 3D cardiac T1 and T1ρ maps with spatial resolution of 2 × 2 × 4 mm were obtained with scan time of 5.4 ± 0.5 min, demonstrating comparable T1 (1236 ± 59 ms) and T1ρ (50.2 ± 2.4 ms) measurements to 2D separate breath-hold mapping techniques. The estimated B1+ maps showed spatial variations across the left ventricle with the septal and inferior regions being 10%-25% lower than the anterior and septal regions. CONCLUSION: The proposed technique achieved efficient 3D joint myocardial T1 and T1ρ mapping at 3T with respiratory motion correction, spin history B1+ correction and water-fat separation.
Qi et al. (Mon,) conducted a other in Healthy (n=10). 3D free-breathing cardiac multi-parametric mapping framework vs. 2D separate breath-hold mapping techniques was evaluated on Myocardial T1 and T1ρ quantification. A novel 3D free-breathing cardiac mapping technique achieved efficient joint myocardial T1 (1236 ± 59 ms) and T1ρ (50.2 ± 2.4 ms) mapping comparable to 2D breath-hold techniques.