Runke Wang1, Suhao Qiu1, Zhiyong Zhang1, and Yuan Feng1
1School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
1School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
A multiphase
radial DENSE sequence was proposed to accelerate the MRE acquisition. The sparsity
of the harmonic motion combined with compressed sensing was used for the reconstruction of undersampled wave images. Phantom and brain images showed a
4-fold acceleration could be achieved.
Figure
2. The reconstruction procedure of the proposed method. In the first step, the acquired
spokes are rearranged to 8 k-spaces belonging to different phase images. The
k-data encoded by negative MEGs are then resorted and concatenated to the data
with positive MEGs encoding to form a pseudo continuous wave. In the second
step, the rearranged k-data are reconstructed simultaneously. The modified TV
transform and temporal FFT are the sparsifying transforms.
Figure
1. Sequence diagram of the MRD-MRE. The motion encoding gradient (MEG) Ge is applied
under a static state and decoded by all the following motion decoding gradients
(MDG) Gdn. With a golden angle radial sampling pattern, the spokes
belonging to different phase offset are acquired continuously and rearranged
after the scan for reconstruction of different phase images. The time interval Δt between the trigger
time and MDG determines the phase offset of each spokes.