Flip-angle modulated 2D-CSE-MRI for motion-robust free-breathing liver PDFF and R2* mapping in a clinical setting

Motivation: Breath-held 3D-CSE-MRI is widely for non-invasive liver fat and iron quantification but is often compromised by respiratory motion. Free-breathing 2D acquisitions using flip-angle modulation (FAM) address this with a short temporal aperture. Goal(s): To assess feasibility, image quality, and performance of 2D-FAM-based free-breathing liver fat and iron quantification in a clinical setting. Approach: 2D-FAM-based proton density fat-fraction and R2* maps were acquired in consecutive patients over an eight month period during routine clinical care, and compared to breath-held 3D-CSE-MRI. Results: In 210 patients, 2D-FAM showed high concordance with commercial 3D-CSE-MRI, yielding superior image quality with limitations in the presence of high iron overload. Impact: The motion robustness and short acquisition time of free-breathing 2D-FAM-CSE-MRI offers significant advantages, enabling reliable quantification of liver fat and iron. This is essential for diagnosis and treatment monitoring of diffuse liver disease, and with potential to improve clinical outcomes.