Reproducibility of tailored and universal non-selective excitation pulses at 7T for human cardiac body imaging: A 3-year and an inter-day study

Motivation: Addressing the issue of reduced spatial variability in flip angle (FA) patterns in ultra-high field 3D imaging of the human heart for inter-year and inter-day studies, ensuring a high level of reproducibility. Goal(s): Find the correct RF parallel transmission (pTx) excitation scheme that reduces FA spatial variability in 7T 3D imaging of the human heart for long-term and short-term studies. Approach: Default, tailored pulses (TP), and pre-computed universal pulses (UP) were evaluated to optimize FA homogeneity in B1+ datasets across three years. Results: The study highlights UPs' robustness in managing FA variations across subjects and coil placements in 3D body imaging at 7T. Impact: This study confirms pre-computed UPs' suitability for 7T cardiac flip angle homogenization. Different MRI operators maintained consistent RF performance across three years and inter-day tests, with no significative differences in scans at various coil positions for both tests.