Jinfeng Tian1, Lance DelaBarre1, John Strupp1, Jay Zhang2, Josef Pfeuffer3, Michael Hamm3, Juergen Nistler3, Kamil Ugurbil1, University of Minnesota University of Minnesota Vaughan1
1Center for Magnetic Resonance, University of Minnesota, Minneapolis, MN, United States; 2Cardiology, University of Minnesota, Minneapolis, MN, United States; 3Siemens Healthcare, Erlangen, Germany
Short RF wavelengths in high field MRI result in less homogeneous |B1+| field and severe SAR gradients in body. To investigate possible solutions, B1 and SAR contours were calculated for ten different 3T whole-body coils. Referenced to a high-pass birdcage body coil, new design permutations included multi-channeled TEM and loop arrays with elements distributed in x, y, and z. RF fields were configured by circular polarization and by B1 shimming. Results showed all arrays with B1 shimming could greatly improve the RF homogeneity while the TEM 2x8 array provides optimal performance based on |B1+| homogeneity, peak SAR and power efficiency.