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Abstract #2818

Slotted Coaxial Cavity Resonator for Head Imaging at Ultra High Fields

Anna Andreychenko1, Alexander J.E. Raaijmakers1, Peter R. Luijten1, Jan J.W. Lagendijk1, Cornelis A.T. van den Berg1

1Imaging Division, UMC Utrecht, Utrecht, Netherlands

Waveguide slot antennas are popular directional antennas used in microwave engineering at UHF (>300 MHz). The operational RF frequency of ultra high field MRI falls into this frequency range. A slotted coaxial cavity resonator with eight independent ports has been designed for human head imaging at 11.7 T. Based on the FDTD simulations, the resonator showed 13 % higher B1+ efficiency than the conventional birdcage head coil when the quadrature phase settings were applied. The presence of eight ports was exploited for effective RF shimming. This design can be a cheap and easily manufactured alternative to the existing coil designs for ultra high field head MRI.

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Keywords

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