Exotic sources of X-rays for iodine K-edge angiography

Abstract

Digital subtractive angiography has been performed to image human coronary arteries using wiggler radiation from electron storage rings. The significant medical promise of this procedure motivates the development of smaller and less costly X-ray sources. Several exotic sources are candidates for consideration, using effects such as Cherenkov, channeling, coherent bremsstrahlung, laser backscattering, microundulator, parametric, Smith-Purcell, and transition radiation. In this work we present an analysis of these effects as possible sources of intense X-rays at the iodine K-edge (33.169 keV). The criteria we use are energy, efficiency, flux, optical properties, and technical realizability. For each of the techniques, we find that they suffer either from low flux, a low energy cutoff, target materials heating, too high electron beam energy requirement, optical mismatch to angiography, or a combination of these. We conclude that the foreseeable state-of-the-art favors a compact storage ring design (H. Wiedemann et al., these Proceedings (8th Nat. Conf. on Synchrotron Radiation Instrumentation, Gaithersburg, MD, USA, 1993) Nucl. Instr. and Meth. A. [1]).