Design of a universal RF-shimming drive mode for head and neck imaging at 7 Tesla using a 16-channel pTx array

We calculate “universal” RF-shimming excitations that provide maximum B1+ coverage and homogeneity across the brain & c-spine using a patient-friendly 16-channel pTx array. We simulated three body models and three z-positions to ensure robustness to both B1+ and SAR variation across a range of head/neck sizes and shapes (universal design). We provide two solutions, both of which may be saved on the scanner: a low-SAR solution that improves flip-angle uniformity by 13% compared to the BC mode excitation (same SAR) and a high-SAR excitation that improves flip-angle non-uniformity by 25% at the cost of a 2x local SAR increase.