Matt Smith with Robert Brown

RF Challenges in High-Field MRI

Using the interaction of nuclear magnetic moments with applied magnetic fields, MRI (magnetic resonance imaging) represents the ability to capture powerful images of anatomical structures. To investigate dynamic processes, such as brain functioning, a more dynamic imaging method, fMRI (functional MRI), can be used that takes advantage of the magnetic susceptibility properties of human tissue. Improvement of the resolution of fMR images is expected in the cutting-edge implementation of higher-strength magnetic fields (and, from resonance matching, higher radiofrequencies to be used in the RF coil part of the MRI system). At higher frequencies, RF coil transmission and detection must be effective with shorter dielectric wavelengths inside the imaged body. This study explores the challenges of designing new RF hardware (using state-of-the art methods of computational electromagnetism) in the light of the new physics regime encountered in the interaction of high frequencies with biological tissue.