Abstract #0099

Joint Design of Dual-Band Large-Tip-Angle RF and Gradient Waveforms in Parallel Excitation

William A. Grissom¹, Adam B. Kerr, Pascal P. Stang², Greig C. Scott², Ileana Hancu³, Mika W. Vogel⁴, John M. Pauly²

¹Electrical Engineering and Radiology, Stanford University, Stanford, CA, United States; ²Electrical Engineering, Stanford University, Stanford, CA, United States; ³GE Global Research, Niskayuna, NY, United States; ⁴Advanced Medical Applications Laboratory, GE Global Research, Munich, Bavaria, Germany

We introduce a new framework for optimizing the phase encoding locations of a 2D or 3D parallel excitation pulse in the large-tip-angle regime. The framework is analogous to the hard pulse approximation, and yields a straightforward analytical relationship between the pulses' spin-domain rotations and the phase encoding locations. This relationship can be exploited to optimize locations using gradient descent, or using optimization transfer for monotonic, parameter-free optimization. We apply our method to the design of dual-band (fat + water) spin echo parallel excitation pulses along 3D rungs trajectories.