Meeting Banner
Abstract #0540

Torus-Shaped Dielectric Resonator for 7T Musculoskeletal Imaging

MAGNA25Johanna J. Bluemink1, Wouter Koning2, Dennis W. Klomp2, Hugo Kroeze2, Stefan Maderwald3, Anke Henning4, Peter R. Luijten2, Jan J.W. Lagendijk1, Cornelis A.T. van den Berg1

1Radiotherapy, University Medical Center Utrecht, Utrecht, Netherlands; 2Radiology, University Medical Center Utrecht, Utrecht, Netherlands; 3Erwin L. Hahn Institute for Magnetic Resonance Imaging, Essen, Germany; 4ETH Zrich, Switzerland

A torus-shaped dielectric resonator is introduced and a proof of concept is given for imaging at 7T. Due to the relatively high frequency of 300 MHz, water can be used as a dielectric while the torus has practical dimensions. Experimental B1+ patterns show good comparison to those obtained in numerical simulations. In-vivo images of the human calf at 7T are obtained using the torus as a transmit/receive coil.

Abstract PDF Presentation Video

Keywords

account amplifier antenna antennas application around arrays arrows axis body calf cavity changing channel channels circular circumference clinical close coil columns concepts conductors configuration constructively copper coronal coverage cross cylinder decrease defined delivered diameter dielectric dimensions dipole discuss distilled dual efficient electrical electron essence evoked except excitation excited experiment experimental experimentally field finite frequencies frequency good gradient harmonic hence human impractical in vivo indicated infinite instead institute introduced investigate larger located long longer loss maps materials medical medium middle minor mode model modeled modes moreover normalized opposite optimized ordinary outer outside part pattern patterns perfect permeability phantom placed plastic positioned power preference propagate propagates quad quadrature radiology radiotherapy radius receive reduce remove resemblance resolution resonator resonators rich rings sample scaling scanners sectional selecting separated setup several shaped shimming sides simulated simulation simulations since solution sometimes source strengths surface taken tape theory torus transmit transmitting transverse types usually view voltage water wave waveguide wide