Enhancing the Motion Robustness of Breath‐Held 3D T1 ‐Weighted Abdominal MRI Using a Cartesian Acquisition With Spiral Profile Ordering

PURPOSE: To develop and validate a novel self-gated motion-robust 3D T1-weighted gradient echo imaging framework based on a Cartesian acquisition with spiral profile ordering (CASPR) for abdominal imaging under unstable breath-hold conditions. METHODS: The CASPR trajectory was evaluated using frequency encoding in the anterior-to-posterior (AP) direction for respiratory motion robustness. The CASPR's intrinsic k-space center oversampling was exploited to directly extract a self-gated respiratory signal from the acquired data. A soft-gating motion compensation framework was integrated into the reconstruction pipeline. The method was validated in 10 healthy volunteers (five males and five females) and compared to a Cartesian acquisition with pseudorandom undersampling. RESULTS: Both CASPR and Cartesian acquisition with pseudorandom undersampling exhibited motion artifacts under unstable breath-hold conditions without retrospective correction. The proposed self-gated CASPR framework enabled reliable extraction of the respiratory signal directly from the AP readout. Soft gating significantly improved the image quality of motion-corrupted scans. CONCLUSION: This study introduces a novel self-gated CASPR-based framework for respiratory motion compensation in 3D abdominal MRI, in cases of incomplete and delayed breath-holds. The method enables the extraction of the self-navigator signal along the anterior-to-posterior axis and compensates for motion using a soft-gating technique.