Novel 2DRF Optimization Framework for Spatially Selective Rf Pulses Incorporating B1, B0 and Variable-Density Trajectory Design

Rainer Schneider¹, ², Dieter Ritter¹, Jens Haueisen², Josef Pfeuffer¹

Echo-planar imaging with a reduced FOV has been often used to increase imaging speed or acquire high-resolution images. However, to date nearly all of the studies use analytically designed pulses neglecting off-resonance effects and B1 inhomogeneity. In this work a 2DRF pulse optimization framework is proposed, which takes individual B0 and B1 maps into account. In addition, a novel trajectory design incorporating off-resonance information is introduced to further tackle geometric distortions. The proposed methods are evaluated with simulated and experimental data. It is shown that optimized 2DRF pulses outperform analytically designed pulses in regard to the overall excitation.