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arXiv · 1505.04149

Direct Imaging of Radio-Frequency Modes via Traveling Wave Magnetic Resonance Imaging

A. Tonyushkin·D. K. Deelchand·P. -F. Van de Moortele·G. Adriany·A. Kiruluta
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Abstract

We demonstrate an experimental method for direct 2D and 3D imaging of magnetic radio-frequency (rf) field distribution in metal-dielectric structures based on traveling wave (TW) magnetic resonance imaging (MRI) at ultra-high field (> 7T). The typical apparatus would include an ultra-high field whole body or small bore MRI scanner, waveguide elements filled with MRI active dielectrics with predefined electric and magnetic properties, and TW rf transmit-receive probes. We validated the technique by obtaining TW magnetic-resonance (MR) images of the magnetic field distribution of the rf modes of circular waveguide filled with deionized water in a 16.4 T small-bore MRI scanner and compared the MR images with numerical simulations. Our MRI technique opens up a practical non-perturbed way of imaging of previously inaccessible rf field distribution of modes inside of various shapes metal waveguides with inserted dielectric objects, including waveguide mode converters and transformers.

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A. Tonyushkin, D. K. Deelchand, P. -F. Van de Moortele, G. Adriany, A. Kiruluta. 2016-01-18. Direct Imaging of Radio-Frequency Modes via Traveling Wave Magnetic Resonance Imaging. https://doi.org/10.1063/1.4940019

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