Comparative study of in-vivo image improvement and dose reduction with dual energy angiography

摘要

The imaging capabilities of the dual energy angiography (DEA) based on the Bragg diffraction on a pyrolitic graphite target and CCD detectors coupled with fiber optic plate with scintillator (FOS) was evaluated using an experimental setup built for phantoms and small animals. The scanning system was built with a new X-ray source, which produces two thin parallel quasi-monochromatic beams starting from a conventional X-ray tube; these beams have peak energies centered before and after the iodine K-edge energy respectively. The polychromatic X-ray beam is monochromatized by Bragg diffraction on a pyrolitic graphite crystal and splitted in two thin parallel beams. The beams go through the phantom and are detected with a CCD coupled with FOS detector. The image results as difference between the remaining intensities of two beams. In this work, we will report results obtained in terms of sensitivity, image quality and dose reduction in comparison with standard angiographic apparatus. In particular, the capability to visualize small vessels will be discussed.