摘要

Dynamic Magnetic Resonance Imaging (DMRI) reconstruction is a challenging theme in image processing. A variety of dimensionality reduction methods using vectorization have been proposed. However, most of them gave rise to a loss of spatial and temporal information. To deal with this problem, this article develops a DMRI reconstruction method in a nonlocal framework by integrating the nonlocal sparse tensor with low-rank tensor regularization. The sparsity constraint employs the Tucker decomposition tensor sparse representation, and the t-product-based tensor nuclear norm is used to set the low-rank constraint. Both constraints are handled in a nonlocal framework, which can take advantage of data redundancy in DMRI. Furthermore, the nonlocal sparse tensor representation we proposed constructs a tensor dictionary in the spatio-temporal dimension, making sparsity more efficient. Consequently, our method can better exploit the multi-dimensional coherence of DMRI data due to its sparsity and lowrankness and the fact that it uses a different tensor decomposition-based method. The Alternating Direction Method of Multipliers (ADMM) has been used for optimization. Experimental results show that the performance of the proposed method is superior to several conventional methods.

全文