Frank Seifert1,2, Tomasz Dawid Lindel1,2, Andr Kuehne1,2, Helmar Waiczies1,2, Wolfgang Renz, 23, Bernd Ittermann1,2
1Physikalisch-Technische Bundesanstalt (PTB), Abbestr. 2-12, D-10587 Berlin, Germany; 2Berlin Ultrahigh Field Facility, Max-Delbrck-Center for Molecular Medicine, D-13125 Berlin, Germany; 3Siemens Healthcare, D-91052 Erlangen, Germany
Tx-SENSE performance depends crucially on the reliable knowledge of the transmit sensitivity maps of the coil elements. For 7T body imaging the virtual reference approach fails to get reliable maps. This was shown for a simulated Tx-SENSE based zoomed cardiac imaging experiment at 7T. FDTD simulations were performed for a experimental 4-channel TX/RX coil array. Using either the virtual reference approach or the true sensitivity maps two sets of RF pulse shapes were calculated for a box like excitation pattern covering the heart. For both RF pulse sets the flip angle distribution was calculated from a full Bloch Equation simulation.