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Abstract #2816

Why Does the Radiative Antenna Have No B1 Twisting at 7T? Framework for and Applications of a Conceptual Mirror Current Model of Coil-Tissue Interactions

Bei Zhang1, Daniel K. Sodickson1, Riccardo Lattanzi1, Graham C. Wiggins1

1The Bernard and Irene Schwartz Center for Biomedical Imaging, NYU Medical Center, New York, United States

In this work, we use simulations and corresponding conceptual arguments to highlight key factors contributing to the presence or absence of asymmetries in RF sensitivity patterns at high field strength. Simple geometrical constructions relating the fields from source currents in coils to the fields from induced eddy or mirror currents in conductive samples elucidate the creation of opposite-sense elliptical polarizations in distinct regions of the sample. This framework is used to explain the observed sensitivity pattern of the recently described radiative antenna, and to understand why it differs from that of other common coil types such as loops and striplines.

Keywords

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