Look-Up Table-Correction for Beam Hardening-Induced Signal of Clinical Dark-Field Chest Radiographs

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Lochschmidt, Maximilian E., Urban, Theresa, Kaster, Lennard, Schick, Rafael, Koehler, Thomas, Pfeiffer, Daniela, Pfeiffer, Franz
Format: Preprint
Veröffentlicht: 2025
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866915768064540672
author Lochschmidt, Maximilian E.
Urban, Theresa
Kaster, Lennard
Schick, Rafael
Koehler, Thomas
Pfeiffer, Daniela
Pfeiffer, Franz
author_facet Lochschmidt, Maximilian E.
Urban, Theresa
Kaster, Lennard
Schick, Rafael
Koehler, Thomas
Pfeiffer, Daniela
Pfeiffer, Franz
contents Background: Material structures at the micrometer scale cause ultra-small-angle X-ray scattering, e.g., seen in lung tissue or plastic foams. In grating-based X-ray imaging, this causes a reduction of the fringe visibility, forming a dark-field signal. Polychromatic beam hardening also changes visibility, adding a false dark-field signal due to attenuation, even in homogeneous, non-scattering materials. Purpose: The objective of this study is to develop a fast, simple, and robust method to correct dark-field signals and bony structures present due to beam hardening on dark-field chest radiographs of study participants. Methods: The method is based on calibration measurements and image processing. Beam hardening by bones and soft tissue is modeled by aluminum and water, respectively, which have no microstructure and thus only generate an artificial dark-field signal. Look-up tables were then created for both. By using a weighted mean of these, forming a single look-up table, and using the attenuation images, the artificial dark-field signal and thus the bone structures present are reduced for study participants. Results: It was found that applying a correction using a weighted look-up table leads to a significant reduction of bone structures in the dark-field image. The weighting of the aluminum component has a substantial impact on the degree to which bone structures remain visible in the dark-field image. Furthermore, a large negative bias in the dark-field image, dependent on the aluminum weighting, was successfully corrected. Conclusions: The beam-hardening-induced signal in the dark-field images was successfully reduced using the method described. The choice of aluminum weighting to suppress rib structures, as well as the selection of bias correction, should be evaluated based on the specific clinical question.
format Preprint
id arxiv_https___arxiv_org_abs_2508_05422
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Look-Up Table-Correction for Beam Hardening-Induced Signal of Clinical Dark-Field Chest Radiographs
Lochschmidt, Maximilian E.
Urban, Theresa
Kaster, Lennard
Schick, Rafael
Koehler, Thomas
Pfeiffer, Daniela
Pfeiffer, Franz
Medical Physics
Applied Physics
Background: Material structures at the micrometer scale cause ultra-small-angle X-ray scattering, e.g., seen in lung tissue or plastic foams. In grating-based X-ray imaging, this causes a reduction of the fringe visibility, forming a dark-field signal. Polychromatic beam hardening also changes visibility, adding a false dark-field signal due to attenuation, even in homogeneous, non-scattering materials. Purpose: The objective of this study is to develop a fast, simple, and robust method to correct dark-field signals and bony structures present due to beam hardening on dark-field chest radiographs of study participants. Methods: The method is based on calibration measurements and image processing. Beam hardening by bones and soft tissue is modeled by aluminum and water, respectively, which have no microstructure and thus only generate an artificial dark-field signal. Look-up tables were then created for both. By using a weighted mean of these, forming a single look-up table, and using the attenuation images, the artificial dark-field signal and thus the bone structures present are reduced for study participants. Results: It was found that applying a correction using a weighted look-up table leads to a significant reduction of bone structures in the dark-field image. The weighting of the aluminum component has a substantial impact on the degree to which bone structures remain visible in the dark-field image. Furthermore, a large negative bias in the dark-field image, dependent on the aluminum weighting, was successfully corrected. Conclusions: The beam-hardening-induced signal in the dark-field images was successfully reduced using the method described. The choice of aluminum weighting to suppress rib structures, as well as the selection of bias correction, should be evaluated based on the specific clinical question.
title Look-Up Table-Correction for Beam Hardening-Induced Signal of Clinical Dark-Field Chest Radiographs
topic Medical Physics
Applied Physics
url https://arxiv.org/abs/2508.05422