title: Numerical comparison of X-ray differential phase contrast and attenuation contrast.
abstract: We present a numerical tool to compare directly the contrast-to-noise-ratio (CNR) of the attenuation- and differential phase-contrast signals available from grating-based X-ray imaging for single radiographs. The attenuation projection is differentiated to bring it into a modality comparable to the differential phase projection using a Gaussian derivative filter. A Relative Contrast Gain (RCG) is then defined as the ratio of the CNR of image values in a region of interest (ROI) in the differential phase projection to the CNR of image values in the same ROI in the differential attenuation projection. We apply the method on experimental data of human breast tissue acquired using a grating interferometer to compare the two contrast modes for two regions of interest differing in the type of tissue. Our results indicate that the proposed method can be used as a local estimate of the spatial distribution of the ratio δ/β, i.e., real and imaginary part of the complex refractive index, across a sample.
authors: Dieter
authors: D
authors: Hahn
authors: Pierre
authors: P
authors: Thibault
authors: Martin
authors: M
authors: Bech
authors: Marco
authors: M
authors: Stockmar
authors: Simone
authors: S
authors: Schleede
authors: Irene
authors: I
authors: Zanette
authors: Alexander
authors: A
authors: Rack
authors: Timm
authors: T
authors: Weitkamp
authors: Aniko
authors: A
authors: Sztrókay
authors: Thomas
authors: T
authors: Schlossbauer
authors: Fabian
authors: F
authors: Bamberg
authors: Maximilian
authors: M
authors: Reiser
authors: Franz
authors: F
authors: Pfeiffer