Direct low-field MRI super-resolution using undersampled k-space
This work addresses the challenge of affordable diagnostic imaging for healthcare by enhancing low-field MRI quality, though it appears incremental as it builds on existing super-resolution and undersampling techniques.
The paper tackles the problem of improving image quality in low-field MRI by proposing a novel framework that reconstructs high-field-like images directly from undersampled k-space, achieving results comparable to full acquisitions and outperforming spatial-domain methods.
Low-field magnetic resonance imaging (MRI) provides affordable access to diagnostic imaging but suffers from prolonged acquisition and limited image quality. Accelerated imaging can be achieved with k-space undersampling, while super-resolution (SR) and image quality transfer (IQT) methods typically rely on spatial-domain post-processing. In this work, we propose a novel framework for reconstructing high-field MR like images directly from undersampled low-field k-space. Our approach employs a k-space dual channel U-Net that processes the real and imaginary components of undersampled k-space to restore missing frequency content. Experiments on low-field brain MRI demonstrate that our k-space-driven image enhancement consistently outperforms the counterpart spatial-domain method. Furthermore, reconstructions from undersampled k-space achieve image quality comparable to full k-space acquisitions. To the best of our knowledge, this is the first work that investigates low-field MRI SR/IQT directly from undersampled k-space.