RF Aspects of High-Field Magnetic Resonance Imaging (HF-MRI): Recent Advances

High-field magnetic resonance imaging (HF-MRI) brings superior imaging with high contrast and signal-to-noise ratio (SNR). For scanning systems higher than 3.0 T and Larmor frequencies above 128 MHz, wavelength and higher tissue conductivity can cause distortion of the electromagnetic fields, leading to degraded image quality. This paper will show current trends in HF-MRI to mitigate some of these issues and provide a linkage between traditional MRI components and novel structures for HF-MRI. Transmit and receive structures, as well as the use of metamaterials for improved excitation and SNR, will be covered. Other examples of these recent trends will be potential antenna structures to replace current coil-based technology, and then finally, receiver/patient protection circuits will be covered.