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Abstract #4418

Application of Rotating RF Coil Array in B1 Shimming with Strict Local SAR Constraints

Jin Jin1, Feng Liu1, Adnan Trakic1, Ewald Weber1, Stuart Crozier2

1University of Queensland, St Lucia, Queensland, Australia; 2The University of Queensland, St Lucia, Queensland, Australia

This work investigated the possibility of using a four-channel mechanically rotating RF coil array (RRFCA) to shim the transmit magnetic fields for high-field MRI, while strictly controlling local specific absorption rate (SAR). Since the numerous available degrees of freedom in both the temporal and the spatial domain are exploited, a notably higher excitation accuracy was achieved compared with the stationary eight-channel phased-array coil. The results of this primarily theoretical study also signify that, since only a low channel count is required, the geometry of RRFCA can be optimised more flexibly to improve field penetration and therefore excitation efficiency and performance.

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Keywords

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