Deep
Low-rank plus Sparse Network for Dynamic MR Imaging
Wenqi Huang1,2, Ziwen Ke1,2, Zhuo-Xu Cui1, Jing Cheng2,3, Zhilang Qiu2,3, Sen Jia3, Yanjie Zhu3, and Dong Liang1,3
1Research Center for Medical AI, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China, 2Shenzhen College of Advanced Technology, University of Chinese Academy of Sciences, Shenzhen, China, 3Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
We propose a model-based low-rank plus
sparse network (L+S-Net) for dynamic MR reconstruction. A learned singular
value thresholding was introduced to explore the deep low rank prior. Experiment
results show that it can improve the reconstruction both qualitatively and
quantitatively.
Fig. 1. The proposed sparse plus low-rank network
(L+S-Net) for dynamic MRI. The L+S-Net is defined by the iterative procedures
of Eq.(5). The three layers correspond to the three modules in L+S-Net, which
are named as low-rank prior layer, sparse prior layer and data consistency layer respectively. The convolution block in sparse prior layer is shown at the left bottom. The correction
term in data consistency layer is shown at the right bottom.
Fig. 3. The reconstruction results of the
different methods (L+S, MoDL and L+S-Net) at 12-fold acceleration using
multi-coil data. The first row shows, from left to right, the ground truth, the
reconstruction result of these methods. The second row shows the enlarged view
of their respective heart regions framed by a yellow box. The third row shows
the error map (display ranges [0, 0.07]). The y-t image (extraction of the 92th
slice along the y and temporal dimensions) and the error of y-t image are also
given for each signal to show the reconstruction performance in the temporal
dimension.