Depletion-Mode GaN HEMT Q-Spoil Switches for MRI Coils

IEEE Trans Med Imaging. 2016 Dec;35(12):2558-2567. doi: 10.1109/TMI.2016.2586053. Epub 2016 Jun 28.

Abstract

Q-spoiling is the process of decoupling an MRI receive coil to protect the equipment and patient. Conventionally, Q-spoiling is performed using a PIN diode switch that draws significant current. In this work, a Q-spoiling technique using a depletion-mode Gallium Nitride HEMT device was developed for coil detuning at both 1.5 T and 3 T MRI. The circuits with conventional PIN diode Q-spoiling and the GaN HEMT device were implemented on surface coils. SNR was measured and compared for all surfaces coils. At both 1.5 T and 3 T, comparable SNR was achieved for all coils with the proposed technique and conventional Q-spoiling. The GaN HEMT device has significantly reduced the required power for Q-spoiling. The GaN HEMT device also provides useful safety features by detuning the coil when unpowered.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Equipment Design
  • Gallium / chemistry*
  • Magnetic Resonance Imaging / instrumentation*
  • Signal-To-Noise Ratio

Substances

  • gallium nitride
  • Gallium