Accelerated Free-Breathing Liver Fat/R2* Quantification in Pediatrics Using XD-GRASP Multi-Echo Stack-of-Radial MRI: A Retrospective Study

Motivation: Free-breathing liver fat and iron quantification is of growing interest in pediatric patients. However, motion compensation is necessary for quantification accuracy, resulting in prolonged acquisition times. Goal(s): This study was to retrospectively evaluate a newly developed technique with XD-GRASP reconstruction in pediatric patients. Approach: Data with oversampled k-space radial views were undersampled to fewer radial views. All data were reconstructed and compared between a self-gating method and the proposed XD-GRASP method. Results: When applied to data with undersampled radial views, the proposed XD-GRASP method reduced image artifacts and improved PDFF and R2* results compared to the self-gating method. Impact: The proposed multi-echo stack-of-radial MRI method using motion-resolved reconstruction and multi-dimensional regularization may allow accelerated free-breathing liver PDFF and R2* mapping in pediatric patients.