A novel magnetic imaging system using time-varying gradients is proposed for the imaging and characterization of atherosclerotic plaque. A sequence of signals are received in the presence of time-varying gradients in all three dimensions. From these signals, high-resolution three-dimensional image information can be derived to provide detailed anatomic information on the geometric structure of the plaque. In addition, these same signals can be further processed to derive specific spectroscopic data on relevant biochemical parameters of the plaque. Using a novel approach to spectral estimation, images are derived of these relevant parameters. Phantoms, animal models and human subjects will be used to verify the derived images with the actual plaque distribution. In vitro NMR will be used with excised plaque to study the spectroscopic characteristics of various forms of plaque and correlate them with the derived spectroscopic images.