Characterization of the phase-contrast radiography edge-enhancement effect in a cabinet x-ray system

Abstract

The purpose of this study was to demonstrate that a commercially available cabinet x-ray system is capable of phase-contrast radiography (PC-R) and to evaluate the effect of different system parameters on the degree of edge enhancement. An acrylic plastic edge phantom was imaged at different tube potentials (25-60 kV) and in different geometries (variable object-to-detector distances, R(2), at a constant source-to-detector distance, R(1) + R(2)). In addition, the effect of noise on the perceived edge enhancement was studied as a function of exposure time. Our results show that a modest degree of phase contrast can be achieved in an unmodified cabinet x-ray system. In addition, the particular system evaluated allowed low-noise PC-R images to be obtained with short (6 s or less) exposures. These results suggest that with appropriate geometric choices PC-R is already available to a wide range of research scientists for use in both small-animal and human-specimen experiments.

The First Analysis and Clinical Evaluation of Native Breast Tissue Using Differential Phase-Contrast Mammography

“…Three patients (2,3,4) were diagnosed with invasive ductal breast carcinoma and 1 patient (5) with invasive lobular carcinoma. Two patients (2, 5) had multicentric, 1 patient (4) multifocal, and 1 patient (3) unifocal malignant diseases.…”

“…[1][2][3][4][5] For negligible anisotropy in the medium, the index of refraction, n, characterizing the optical properties of a tissue, can be expressed in its complex form: n ϭ 1 Ϫ ␦ ϩ i␤, where ␦ is the decrement of the real part of the refractive index responsible for the phase shift, whereas the imaginary part, ␤, describes the attenuation properties of the material. So far, in clinical applications like radiography, mammography, or computed tomography, only x-ray attenuation-described by ␤-is used for image generation.…”

Effects of Tube Voltage on Phase-Contrast Imaging for Different Microfocus X-Ray Tubes

“…From this way, we can see that longer wavelengths (lower x-ray energies), longer SOD distances and smaller focus-spot sizes, are beneficial for the phase-contrast imaging. Donnelly investigated some influencing factors by experiments based on different PCI systems [4][5][6]. It is interesting that Donnelly showed that phase enhancement effect had a slightly drop with the increasing of tube voltage (kVp) in this paper [4], but the author also showed a different result that phase enhancement effect essentially wasn't affected as the tube voltage increased in other two papers [5,6].…”

Phase imaging using polycapillary optics

“…The conspicuity of the edge enhancement 6 can be described by the edge-enhancement to noise ratio (EE/N) ratio ̅ (8) where P is the peak intensity, ̅ is the average intensity over a region of background labeled B in Figure 7, and is the standard deviation of intensity over region B. The edge-enhancement to noise ratio was 0.91.…”