Priti Balchandani1, John Pauly2, Daniel Spielman1
1Radiology, Stanford University, Stanford, CA, USA; 2Electrical Engineering, Stanford University, Stanford, CA, USA
We present a new, systematic method for designing adiabatic RF pulses that utilizes the Shinnar Le-Roux (SLR) algorithm for pulse design. By overlaying a sufficient amount of quadratic phase across the spectral profile prior to the inverse SLR transform, we generate RF pulses that exhibit the required spectral characteristics as well as adiabatic behavior. The addition of quadratic phase distributes RF energy more uniformly, resulting in reduced SAR pulses. The method enables the pulse designer to specify spectral profile parameters and the degree of quadratic phase. Simulations and phantom experiments demonstrate that pulses generated using this new method behave adiabatically.