UNC-CH Physics and Astronomy Colloquium

Wilson Miller, University of Virginia

“MRI illuminated by Gamma Rays”

Most medical imaging modalities have roots in old-fashioned nuclear physics. Magnetic Resonance Imaging (MRI), which is based on the spin dynamics of oriented nuclei, provides exquisite spatial and spectral resolution plus a rich variety of contrast mechanisms for visualizing disease states in the human body. Nuclear Imaging, which uses gamma cameras to detect energetic photons emitted during nuclear transitions, allows tracking of small quantities of radioactive tracers that seek particular disease targets within the body. My research group is developing what we hope will become a new medical imaging modality, that combines the spatial/spectral resolution of MRI with the detection sensitivity of nuclear imaging. This new modality, which we refer to as Polarized Nuclear Imaging, takes advantage of the fact that nuclear isomers with spin > ½ emit gamma rays in a spatially anisotropic pattern with respect to their spin orientation. The result is a fundamentally new imaging technique with some surprising properties. In this talk, I will describe the evolution of this (potentially) promising new imaging modality, from its origins in old-fashioned nuclear physics to the significant practical challenges that will ultimately determine whether its promise is ever fulfilled.