IFR-Net: Iterative Feature Refinement Network for Compressed Sensing MRI
This addresses reconstruction quality and speed limitations in medical imaging for MRI practitioners, representing an incremental improvement over their previous iterative method.
The authors tackled the problem of fine structure loss in compressed sensing MRI under high acceleration factors by proposing IFR-Net, an unrolled network that trains regularization parameters and feature refinement operators, achieving strong detail capture and structural preservation with fast reconstruction speed.
To improve the compressive sensing MRI (CS-MRI) approaches in terms of fine structure loss under high acceleration factors, we have proposed an iterative feature refinement model (IFR-CS), equipped with fixed transforms, to restore the meaningful structures and details. Nevertheless, the proposed IFR-CS still has some limitations, such as the selection of hyper-parameters, a lengthy reconstruction time, and the fixed sparsifying transform. To alleviate these issues, we unroll the iterative feature refinement procedures in IFR-CS to a supervised model-driven network, dubbed IFR-Net. Equipped with training data pairs, both regularization parameter and the utmost feature refinement operator in IFR-CS become trainable. Additionally, inspired by the powerful representation capability of convolutional neural network (CNN), CNN-based inversion blocks are explored in the sparsity-promoting denoising module to generalize the sparsity-enforcing operator. Extensive experiments on both simulated and in vivo MR datasets have shown that the proposed network possesses a strong capability to capture image details and preserve well the structural information with fast reconstruction speed.