Respiratory motion-corrected model-based 3D water-fat MRA at 0.55T

Motivation: Navigator-gated MRAs often have unpredictable scan times, limiting practicality. Achieving robust fat suppression remains challenging at 0.55T. Goal(s): Develop a 5-minute MRA at 0.55T with predictable scan time, 100% data efficiency, and reliable water/fat separation, comparable to navigator-gated results. Approach: Use self-gating to infer motion bins and apply model-based Dixon reconstruction with motion correction for direct water/fat imaging. Compare results to navigator-gated acquisitions with image-based water-fat separation. Results: The proposed method offers comparable image quality, 100% efficiency, and predictable scan time, while avoiding navigator-induced saturation effects. Impact: An MRA at 0.55T covering the entire thorax, allowing water/fat separation without navigator artefacts can be achieved in a predictable time of 5 minutes.