Niravkumar Darji1,
Kyoung-Nam Kim2, Gopesh Patel1, Hans-Peter Fautz3,
Johannes Bernarding2, Oliver Speck1
1Biomedical
Magnetic Resonance, Otto-von-Guericke University, Magdeburg, Saxony Anhalt,
Germany; 2Institute for Biometry & Medicine Informatics, Otto-von-Guericke
University, Magdeburg, Saxony Anhalt, Germany; 3 Siemens
Healthcare, Erlangen, Germany
Human MR System equipped with a multi Tx hardware typically have a much smaller number of Tx channels than Receive (Rx) channels. The purpose of this study was to evaluate whether more of Tx channels could improve the Tx field performance. B1+ field inhomogeneity at 7T can be minimized to a certain level by varying the phase and amplitude of individual channels of the 16 channel transmit array. However, even with a larger number of channels, complex B1+ distributions cannot be corrected by means of static RF-shimming only. Transmit-SENSE with spoke trajectories may be more efficient in correcting inhomogeneities even with a lower number of channels.
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