Multi-Scanner Repeatability and Reproducibility of quadratic RF phase MRF Breath-held and Free-breathing with Pilot Tone

Motivation: Ensuring independent agreement using breath-hold (BH) and free-breathing with Pilot Tone (PT) quadratic RF phase Magnetic Resonance Fingerprinting (qRF-MRF) in abdomen. Goal(s): Show repeatability and reproducibility of T1, T2, and T2* maps generated using BH and free-breathing with PT qRF-MRF. Approach: qRF-MRF scan-rescan of 2D-axial abdominal slices performed across two same-site Siemens 3T scanners. Reconstructions analyzed through liver ROIs and compared in Bland-Altman plots for repeatability and reproducibility. Results: Bland-Altman results show good agreement, low bias for resulting reconstructed BH and PT qRF-MRF T1, T2, and T2* results between inter- and intra-scanner results and between BH and PT scans. Impact: The independence of qRF-MRF fidelity, despite repeat scans or different scanner usage, is important for adopting into a clinical workflow. This study demonstrates this through the repeatability and reproducibility of breath-hold qRF-MRF and free-breathing qRF-MRF with pilot tone (PT).