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Quantitative comparison between two phase contrast techniques: diffraction enhanced imaging and phase propagation imaging.

Elodie Pagot·Stefan Fiedler·Peter Cloetens·Alberto Bravin·Paola Coan·Kamel Fezzaa·José Baruchel·Jürgen Härtwig·Karl von Smitten·Marjut Leidenius·Marja-Liisa Karjalainen-Lindsberg·Jani Keyriläinen
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Abstract

Two x-ray phase contrast imaging techniques are compared in a quantitative way for future mammographic applications: diffraction enhanced imaging (DEI) and phase propagation imaging (PPI). DEI involves, downstream of the sample, an analyser crystal acting as an angular filter for x-rays refracted by the sample. PPI simply uses the propagation (Fresnel diffraction) of the monochromatic and partially coherent x-ray beam over large distances. The information given by the two techniques is assessed by theoretical simulations and compared at the level of the experimental results for different kinds of samples (phantoms and real tissues). The imaging parameters such as the energy, the angular position of the analyser crystal in the DEI case or the sample to detector distance in the PPI case were varied in order to optimize the image quality in terms of contrast, visibility and figure of merit.

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Breast NeoplasmsCalcinosisHumansMammographyPhantoms, ImagingRadiographic Image EnhancementRadiographic Image Interpretation, Computer-AssistedReproducibility of ResultsSensitivity and SpecificityX-Ray DiffractionComparative StudyEvaluation StudyJournal Article

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Elodie Pagot, Stefan Fiedler, Peter Cloetens, Alberto Bravin, Paola Coan, Kamel Fezzaa, José Baruchel, Jürgen Härtwig, Karl von Smitten, Marjut Leidenius, Marja-Liisa Karjalainen-Lindsberg, Jani Keyriläinen. 2005-02-21. Quantitative comparison between two phase contrast techniques: diffraction enhanced imaging and phase propagation imaging.. https://doi.org/10.1088/0031-9155%2F50%2F4%2F010

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