A theoretical framework for comparing noise characteristics of spectral, differential phase-contrast and spectral differential phase-contrast X-ray imaging.

A theoretical framework for comparing noise characteristics of spectral, differential phase-contrast and spectral differential phase-contrast X-ray imaging.
Phys Med Biol. 2020 Jan 28;:
Authors: Mechlem K, Sellerer T, Viermetz M, Herzen J, Pfeiffer F
Abstract
Spectral and grating-based differential phase-contrast X-ray imaging are two emerging technologies that offer additional information compared with conventional attenuation-based X-ray imaging. In the case of spectral imaging, energy-resolved measurements allow the generation of material-specific images by exploiting differences in the energy-dependent attenuation. Differential phase-contrast imaging uses the phase shift that an X-ray wave exhibits when traversing an object as contrast generation mechanism. Recently, we have investigated the combination of these two imaging techniques (spectral differential phase-contrast imaging) and demonstrated potential advantages compared with spectral imaging. In this work, we present a noise analysis framework that allows the prediction of (co-) variances and noise power spectra for all three imaging methods. Moreover, the optimum acquisition parameters for a particular imaging task can be determined. We use this framework for a performance comparison of all three imaging methods. The comparison is focused on (projected) electron density images since they can be calculated with all three imaging methods. Our study shows that spectral diffe...

Source: Physics in Medicine and Biology - January 27, 2020 Category: Physics Authors: Mechlem K, Sellerer T, Viermetz M, Herzen J, Pfeiffer F Tags: Phys Med Biol Source Type: research