Quantitative MR T1 measurements with TOWERS: T-One with enhanced robustness and speed

T1 mapping can be beneficial for many applications in magnetic resonance imaging. Such applications include sequence optimization, clinical utility and tissue segmentation. However, the methods in the T1 mapping literature proposed to date either take a great deal of time to acquire or suffer from fundamental shortcomings. In addition, if significant motion occurs even once early in the scan, the operator needs to rerun the sequence, which is costly and time-consuming. Therefore, it is desirable to design a sequence that is not only fast, but also reliable to yield a good-quality T1 map, even in the presence of motion. In this study, we propose an EPI-based sequence with an efficient slice reordering scheme introduced relatively recently. The proposed sequence acquires saturation recovery samples that not only help improve estimation accuracy, but also serve as references for estimating motion parameters that will be used for mitigating the effects of motion. Furthermore, the reconstruction parameters are updated in the middle and at the end of the scan, and are used to retrospectively correct for motion. Phantom and in vivo experiments show the promise of the method.Doctor of Philosoph