Franciszek Hennel1, Sascha Khler1, Martin Janich2
1Bruker BioSpin MRI, Ettlingen, Germany; 2Intitute of Biomedical Engineering, University of Karlsruhe, Germany
A method for 3D mapping of the radio-frequency field magnitude (B1) is proposed based on the adiabatic half-passage 90-degree excitation. The adiabatic pulse starts the frequency sweep on resonance and generates a pure transverse magnetization with the phase strongly dependent on B1. The method has been applied to map the B1 field of a surface transmit-coil and provided a superior dynamic range compared to the amplitude-based B1-mapping methods.