TY - JOUR
T1 - A unified Maximum Likelihood framework for simultaneous motion and T1 estimation in quantitative MR T1 mapping
AU - Ramos-Llorden, Gabriel
AU - Den Dekker, Arnold J.
AU - Van Steenkiste, Gwendolyn Van
AU - Jeurissen, Ben
AU - Vanhevel, Floris
AU - Audekerke, Johan Van
AU - Verhoye, Marleen
AU - Sijbers, Jan
N1 - Accepted Author Manuscript
PY - 2017
Y1 - 2017
N2 - In quantitative MR T1 mapping, the spin-lattice relaxation time T1 of tissues is estimated from a series of T1-weighted images. As the T1 estimation is a voxel-wise estimation procedure, correct spatial alignment of the T1-weighted images is crucial. Conventionally, the T1-weighted images are first registered based on a general-purpose registration metric, after which the T1 map is estimated. However, as demonstrated in this paper, such a two-step approach leads to a bias in the final T1 map. In our work, instead of considering motion correction as a preprocessing step, we recover the motion-free T1 map using a unified estimation approach. In particular, we propose a unified framework where the motion parameters and the T1 map are simultaneously estimated with a Maximum Likelihood (ML) estimator. With our framework, the relaxation model, the motion model as well as the data statistics are jointly incorporated to provide substantially more accurate motion and T1 parameter estimates. Experiments with realistic Monte Carlo simulations show that the proposed unified ML framework outperforms the conventional two-step approach as well as state-of-the-art modelbased approaches, in terms of both motion and T1 map accuracy and mean-square error. Furthermore, the proposed method was additionally validated in a controlled experiment with real T1-weighted data and with two in vivo human brain T1-weighted data sets, showing its applicability in real-life scenarios.
AB - In quantitative MR T1 mapping, the spin-lattice relaxation time T1 of tissues is estimated from a series of T1-weighted images. As the T1 estimation is a voxel-wise estimation procedure, correct spatial alignment of the T1-weighted images is crucial. Conventionally, the T1-weighted images are first registered based on a general-purpose registration metric, after which the T1 map is estimated. However, as demonstrated in this paper, such a two-step approach leads to a bias in the final T1 map. In our work, instead of considering motion correction as a preprocessing step, we recover the motion-free T1 map using a unified estimation approach. In particular, we propose a unified framework where the motion parameters and the T1 map are simultaneously estimated with a Maximum Likelihood (ML) estimator. With our framework, the relaxation model, the motion model as well as the data statistics are jointly incorporated to provide substantially more accurate motion and T1 parameter estimates. Experiments with realistic Monte Carlo simulations show that the proposed unified ML framework outperforms the conventional two-step approach as well as state-of-the-art modelbased approaches, in terms of both motion and T1 map accuracy and mean-square error. Furthermore, the proposed method was additionally validated in a controlled experiment with real T1-weighted data and with two in vivo human brain T1-weighted data sets, showing its applicability in real-life scenarios.
KW - dynamic MRI
KW - Maximum Likelihood
KW - motion correction
KW - Registration
KW - T1 mapping
UR - http://resolver.tudelft.nl/uuid:a25975c4-2569-4b73-8657-7702e94c5990
UR - http://www.scopus.com/inward/record.url?scp=84991695794&partnerID=8YFLogxK
U2 - 10.1109/TMI.2016.2611653
DO - 10.1109/TMI.2016.2611653
M3 - Article
SN - 0278-0062
VL - 36
SP - 433
EP - 446
JO - IEEE Transactions on Medical Imaging
JF - IEEE Transactions on Medical Imaging
IS - 2
ER -