Ultra-short-TR FlamingFIESTA enhances robustness of matrix-pencil functional lung MRI in pediatric cystic fibrosis patients on 1.5T GE systems

Motivation: Fast time-resolved bSSFP acquisitions have shown promise for contrast agent-free functional lung MRI. Due to the off-resonance sensitivity of bSSFP, successful application of this technique requires a sufficiently short TR. Goal(s): To enable access to reliable contrast agent-free functional pulmonary MRI based on matrix-pencil decomposition for pediatric patients on 1.5T GE MR scanners. Approach: A dynamic 2D ultra-short-TR bSSFP sequence termed FlamingFIESTA is implemented and tailored for functional lung scans, which eliminates real-time overhead based on a packed-TR acquisition scheme. Results: A 24% TR reduction could be achieved relative to the GE product sequence, yielding high-quality base images and improved functional data. Impact: Ultra-short-TR FlamingFIESTA imaging considerably improves image quality and consequently functional outcome of matrix-pencil pulmonary MRI on 1.5T GE systems. This constitutes a crucial step to expand access to matrix-pencil MRI and provide a contrast agent-free alternative for chronically ill patients.