Fast updating in MRI via multiscale localization

In this paper we introduce an algorithm for fast updating of projection reconstruction MRI images. This algorithm makes use of range characterizations of the Radon transform, and sampling techniques of computerized tomography. Our algorithm differs from other attempts to image time-varying phenomena in that it does not average over time, but rather localizes in time for 'snap-shot' imaging. This uses the fact that image features from different scales can be updated at different rates. We also introduce a technique for spatial localization of MRI data. This technique shows promise for fast updating of locally changing phenomena in MR. Clinical applications of this technique include dynamic imaging of time dependent physiological processes like oxygen usage and blood flow in the brain.