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Abstract #4379

Manipulating B1 Spatial Distribution at 7 Tesla with Dielectric Pads at a Distance from a Transmit Surface Coil

Manushka V. Vaidya1, 2, Sukhoon Oh1, Christopher Michael Collins1, 2, Daniel K. Sodickson1, 2, Riccardo Lattanzi1, 2

1Bernard and Irene Schwartz Center for Biomedical Imaging,, New York University School of Medicine, New York, NY, United States; 2Sackler Institute of Graduate Biomedical Sciences, New York University School of Medicine, New York, NY, United States

The use of dielectric pads between the radiofrequency (RF) coil and sample has been proposed to focus the B1 field into the sample to improve transmit efficiency. In this study, we investigated how dielectric pads placed at a distance from the RF coil affect the B1+ spatial distribution inside the sample. We performed numerical simulations of the B1+ distribution inside a uniform cylinder at 7T for various positions of the dielectric pad with and without a surrounding shield. Manipulating B1 spatial distribution with dielectric pads can be advantageous for various MR applications, including improving RF homogeneity at ultra-high fields.

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Keywords

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