COOL TOOLS
A specialized antenna
Story by Connie Bryson/Photo by Laughing Dog Photography
Its proper name is a radio-frequency head coil and it is used for magnetic resonance (MR) imaging of the human brain, but AHFMR Senior Scholar Dr. Alan Wilman calls this device "the final piece of the puzzle." The puzzle in question is the array of equipment required for the 4.7-tesla magnet in the Peter S. Allen MR Research Centre at the University of Alberta Hospital. (A tesla is a standard measure of the intensity of a magnetic field.) It is the strongest of three MR imaging systems in the centre, and one of only two very high field systems in Canada. It generates a magnetic field that is three times larger than the 1.5 tesla magnets in everyday clinical use. "Because this is such a unique MR system, we needed to purchase very specialized equipment," says Dr. Wilman. The radio-frequency head coil is the last major purchase, and one of the most important. The coil is placed around the head of a person in the scanner and acts as a kind of antenna to detect radio waves from hydrogen atoms in the brain, which have been polarized by the large magnetic field. "The 4.7 magnet can deliver images that have very high resolution, but only if we have a really good receiver. That's why the new coil is such a critical element," explains Dr. Wilman. "It is enabling leading-edge basic research on the brain as well as clinical research on brain disorders including stroke, multiple sclerosis, epilepsy, and Parkinson's disease."