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Abstract #0535

B1 Shimming with a Multi-Mode Travelling Wave Antenna at 9.4T

Daniel Brenner1, Frank Geschewski1, Jrg Felder1, Kaveh Vahedipour1, Tony Stcker1, N. Jon Shah1, 2

1Institute of Neuroscience and Medicine - 4, Forschungszentrum Jlich, Jlich, Germany; 2JARA - Faculty of Medicine, RWTH Aachen University, Aachen, Germany

Travelling waves have been introduced as an alternative excitation technique for UHF MRI. Recently, the extension to multi-channel excitation was presented at 7T using dielectric fillings of the magnet bore. At 9.4T (~400MHz), to excite multiple modes without the necessity of such a dielectric filing becomes feasible. Building on initial performance measurements of the multi-mode antenna this work shows the prospects of RF shimming with the multi-mode antenna. The RF shimming is capable of reducing localised RF inhomogeneities in a phantom experiment. Though it cannot completely overcome the problem of B1 dropouts.

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Keywords

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