Automatic respiratory and bulk patient motion corrected (ACROBATIC) free-running whole-heart 5D MRI

Motivation: Patient bulk motion remains a challenge in free-running 5D whole-heart imaging, as it can degrade image quality, limit diagnostic accuracy, and necessitate repeat scanning. Goal(s): To develop and validate a framework for automatic respiratory and bulk patient motion corrected (ACROBATIC) whole-heart 5D MRI. Approach: Free-running ferumoxytol-enhanced data were retrospectively reconstructed into dynamic images, with each frame representing one respiratory cycle. Intra-bin motion was corrected using focused navigation, followed by 3D rigid registration and outlier rejection to quantify and correct bulk motion, yielding cardiac and respiratory motion-resolved 5D images. Results: Developed method improves sharpness in 5D whole-heart MR-acquisitions affected by bulk motion. Impact: Bulk motion correction in ferumoxytol-enhanced free-running 5D whole-heart MRI enhances image quality in patients, moving during the acquisition, by accounting for respiratory displacement and rigid bulk motion while rejecting outliers. This could reduce the need for sedation, particularly in pediatrics.