MR Image Enhancement with High Permittivity Materials

Open Access
Author:
Ketterman, Matthew David
Graduate Program:
Engineering Science
Degree:
Master of Engineering
Document Type:
Master Thesis
Date of Defense:
February 27, 2015
Committee Members:
  • Michael T Lanagan, Thesis Advisor
  • Thomas Neuberger, Thesis Advisor
  • Judith Todd, Thesis Advisor
  • Corina Stefania Drapaca, Thesis Advisor
Keywords:
  • MRI
  • magnetic resonance imaging
  • high permittivity
  • materials
  • electromagnetics
Abstract:
Magnetic Resonance Imaging (MRI) B_1 field magnification and sculpting is made possible with the introduction of high permittivity materials such as Barium Titanate. For several years, brightening and darkening phenomena have emerged under various percepts such as wavelength effects, dielectric resonance, and constructive interference. Technicians have often shared techniques such as the implementation of water pads in order to restore homogeneity or otherwise brighten some region of interest (ROI). Advancing upon such techniques with high permittivity materials, and by thoroughly modeling the resonance condition, an emerging explanation of the aforementioned phenomena is developed into several distinct and novel models and advancement applications. Herein, constructs are developed that permit magnetic field peak positioning, amplification, and increases of magnetic to electric field ratio. Through this becoming technology, it may now be possible to substantially increase signal-to-noise ratio (SNR), decrease specific absorption rate (SAR), and lower overall scan time. Prototypes are appended to the modeling section.