Edward Hawkins with Hiroyuki Fujita, Xiaoyu Yang & Robert Brown

Constructing a Birdcage Coil, Facilitating Freedom from the MRI Cage

Magnetic Resonance Imaging (MRI) represents the marriage of medicine and physics, producing images of the human body which are astoundingly accurate while employing only non-invasive shifting magnetic fields as detectors. Because the idea for medical imaging evolved from applying spatial mapping to existing Nuclear Magnetic Resonance (NMR) technology only a few decades ago, MRI has typically been performed with immense and intimidating machines which surround the person being imaged. Also, to accumulate the best images, an ideal subject would be motionless and extremely cold, both of which are at odds with imaging a living person. To better fit the special conditions ideal for imaging people, the need is great for more specialized coils. One particularly pertinent idea is to insert a microcoil in a catheter and use it to image blood vessels and other tubes within the body in vivo . Before clinical trials of prototypes can begin, images of blood vessels from cadavers must be validated using a more conventional external coil. While there are many possibilities, the birdcage coil is an elegant choice because of its uniquely uniform internal field; it is especially efficient at increasing the signal to noise ratio (SNR) because this field is tuned to rotate at the frequency of hydrogen atoms precessing in the large static magnetic field used in imaging. This project will numerically simulate, construct, and tune a birdcage coil for use in testing prototype microcoils. In so doing, we hope to uncover peculiar and new aspects of the problem of imaging the singularly difficult human physiology.