Wireless video transmission into the MRI magnet room: implementation and evaluation at 1.5T, 3T and 7T

Biomed Tech (Berl). 2019 Aug 27;64(4):373-382. doi: 10.1515/bmt-2018-0073.

Abstract

Purpose To analyze the interference between a wireless high definition multimedia interface (WHDMI) and magnetic resonance imaging (MRI) image quality at 1.5T, 3T and 7T. Materials and methods A wireless video transmission system (WVTS) consisting of a WHDMI and a projector was used to transmit and display a video stream into the magnet room. MR image quality was analyzed at 1.5T, 3T and 7T. Signal-to-noise-ratio (SNR¯) $(\overline {{\rm{SNR}}} )$ and radio frequency (RF)-noise spectrum were measured at three transmitter positions (A: inside the cabin, B: in front of the waveguide and C: in the control room). WVTS system functionality tests included measurements of reliability, delay and image quality. Results With the WVTS mean SNR¯ $\overline {{\rm{SNR}}} $ values significantly decreased in comparison to the reference for all positions and fieldstrenghts, while the spectra's baseline is elevated at 1.5T and 3T. Peaks related to continuous wave interferences are apparent at all field strenghts. For WHDMI alone mean SNR¯ $\overline {{\rm{SNR}}} $ values were stable without significant differences to the reference. No elevation of the spectra's baseline could be observed. Functionality measurements confirmed high connection reliability with stable image quality and no delays for all field strengths. Conclusion We conclude that wireless transmission of video streams into the MRI magnet room is feasible at all field strengths without hampering image quality.

Keywords: MR-guided interventions; MRI; data transmission; fMRI; interventional MRI; wireless video transmission.

MeSH terms

  • Humans
  • Image Processing, Computer-Assisted / methods*
  • Magnetic Resonance Imaging / methods*
  • Magnets
  • Radio Waves
  • Reproducibility of Results
  • Signal-To-Noise Ratio