In-vivo dark-field and phase-contrast x-ray imaging

Abstract In this study we aim to evaluate the assessment of bronchial pathologies in a murine model of lung transplantation with grating-based X-ray interferometry in vivo. Imaging was performed using a dedicated grating-based small-animal X-ray dark-field and phase-contrast scanner. While the contrast modality of the dark-field signal already showed several promising applications for diagnosing various types of pulmonary diseases, the phase-shifting contrast mechanism of the phase contrast has not yet been evaluated in vivo. For this purpose, qualitative analysis of phase-contrast images was performed and revealed pathologies due to previous lung transplantation, such as unilateral bronchial stenosis or bronchial truncation. Dependent lung parenchyma showed a strong loss in dark-field and absorption signal intensity, possibly caused by several post transplantational pathologies such as atelectasis, pleural effusion, or pulmonary infiltrates. With this study, we are able to show that bronchial pathologies can be visualized in vivo using conventional X-ray imaging when phase-contrast information is analysed. Absorption and dark-field images can be used to quantify the severity of lack of ventilation in the affected lung.

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Applying the Fokker–Planck equation to grating-based x-ray phase and dark-field imaging

Scientific Reports ◽

10.1038/s41598-019-52283-6 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 6

Author(s):

Kaye S. Morgan ◽

David M. Paganin

Keyword(s):

Phase Contrast ◽

Speckle Pattern ◽

Planck Equation ◽

Dark Field ◽

Structured Illumination ◽

X Ray ◽

Fokker Planck Equation ◽

X Ray Imaging ◽

Phase Signal ◽

Fokker Planck

AbstractX-ray imaging has conventionally relied upon attenuation to provide contrast. In recent years, two complementary modalities have been added; (a) phase contrast, which can capture low-density samples that are difficult to see using attenuation, and (b) dark-field x-ray imaging, which reveals the presence of sub-pixel sample structures. These three modalities can be accessed using a crystal analyser, a grating interferometer or by looking at a directly-resolved grid, grating or speckle pattern. Grating and grid-based methods extract a differential phase signal by measuring how far a feature in the illumination has been shifted transversely due to the presence of a sample. The dark-field signal is extracted by measuring how the visibility of the structured illumination is decreased, typically due to the presence of sub-pixel structures in a sample. The strength of the dark-field signal may depend on the grating period, the pixel size and the set-up distances, and additional dark-field signal contributions may be seen as a result of strong phase effects or other factors. In this paper we show that the finite-difference form of the Fokker–Planck equation can be applied to describe the drift (phase signal) and diffusion (dark-field signal) of the periodic or structured illumination used in phase contrast x-ray imaging with gratings, in order to better understand any cross-talk between attenuation, phase and dark-field x-ray signals. In future work, this mathematical description could be used as a basis for new approaches to the inverse problem of recovering both phase and dark-field information.

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In vivo Dynamic Phase-Contrast X-ray Imaging using a Compact Light Source

Scientific Reports ◽

10.1038/s41598-018-24763-8 ◽

2018 ◽

Vol 8 (1) ◽

Cited By ~ 9

Author(s):

Regine Gradl ◽

Martin Dierolf ◽

Benedikt Günther ◽

Lorenz Hehn ◽

Winfried Möller ◽

...

Keyword(s):

Light Source ◽

Phase Contrast ◽

X Ray ◽

Dynamic Phase ◽

X Ray Imaging ◽

Compact Light Source

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Experimental validation of image contrast correlation between ultra-small-angle X-ray scattering and grating-based dark-field imaging using a laser-driven compact X-ray source

Photonics and Lasers in Medicine ◽

10.1515/plm-2011-0012 ◽

2012 ◽

Vol 1 (1) ◽

Cited By ~ 12

Author(s):

Martin Bech ◽

Simone Schleede ◽

Guillaume Potdevin ◽

Klaus Achterhold ◽

Oliver Bunk ◽

...

Keyword(s):

Small Angle ◽

Phase Contrast ◽

Dark Field ◽

X Ray ◽

Dark Field Imaging ◽

X Ray Scattering ◽

X Ray Imaging ◽

Grating Interferometer ◽

Complementary Image ◽

Ray Scattering

AbstractX-ray phase and dark-field contrast have recently been the source of much attention in the field of X-ray imaging, as they both contribute new imaging signals based on physical principles that differ from conventional X-ray imaging. With a so-called Talbot grating interferometer, both phase-contrast and dark-field images are obtained simultaneously with the conventional attenuation-based X-ray image, providing three complementary image modalities that are intrinsically registered. Whereas the physical contrast mechanisms behind attenuation and phase contrast are well understood, a formalism to describe the dark-field signal is still in progress. In this article, we report on correlative experimental results obtained with a grating interferometer and with small-angle X-ray scattering. Furthermore, we use a proposed model to quantitatively describe the results, which could be of great importance for future clinical and biomedical applications of grating-based X-ray imaging.

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Principles of Different X-ray Phase-Contrast Imaging: A Review

Applied Sciences ◽

10.3390/app11072971 ◽

2021 ◽

Vol 11 (7) ◽

pp. 2971

Author(s):

Siwei Tao ◽

Congxiao He ◽

Xiang Hao ◽

Cuifang Kuang ◽

Xu Liu

Keyword(s):

Biological Samples ◽

Phase Contrast ◽

Recent Progress ◽

Phase Contrast Imaging ◽

Contrast Imaging ◽

X Ray ◽

X Ray Imaging ◽

Internal Structures ◽

X Ray Absorption ◽

Made In

Numerous advances have been made in X-ray technology in recent years. X-ray imaging plays an important role in the nondestructive exploration of the internal structures of objects. However, the contrast of X-ray absorption images remains low, especially for materials with low atomic numbers, such as biological samples. X-ray phase-contrast images have an intrinsically higher contrast than absorption images. In this review, the principles, milestones, and recent progress of X-ray phase-contrast imaging methods are demonstrated. In addition, prospective applications are presented.

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Correlation of image quality parameters with tube voltage in X-ray dark-field chest radiography: a phantom study

Scientific Reports ◽

10.1038/s41598-021-93716-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Andreas P. Sauter ◽

Jana Andrejewski ◽

Manuela Frank ◽

Konstantin Willer ◽

Julia Herzen ◽

...

Keyword(s):

Image Quality ◽

Imaging Modality ◽

Signal Strength ◽

Dark Field ◽

Tube Voltage ◽

X Ray ◽

Dose Area Product ◽

Dark Field Imaging ◽

Field Imaging

AbstractGrating-based X-ray dark-field imaging is a novel imaging modality with enormous technical progress during the last years. It enables the detection of microstructure impairment as in the healthy lung a strong dark-field signal is present due to the high number of air-tissue interfaces. Using the experience from setups for animal imaging, first studies with a human cadaver could be performed recently. Subsequently, the first dark-field scanner for in-vivo chest imaging of humans was developed. In the current study, the optimal tube voltage for dark-field radiography of the thorax in this setup was examined using an anthropomorphic chest phantom. Tube voltages of 50–125 kVp were used while maintaining a constant dose-area-product. The resulting dark-field and attenuation radiographs were evaluated in a reader study as well as objectively in terms of contrast-to-noise ratio and signal strength. We found that the optimum tube voltage for dark-field imaging is 70 kVp as here the most favorable combination of image quality, signal strength, and sharpness is present. At this voltage, a high image quality was perceived in the reader study also for attenuation radiographs, which should be sufficient for routine imaging. The results of this study are fundamental for upcoming patient studies with living humans.

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Visualization Ability of Phase-Contrast Synchrotron-Based X-Ray Imaging Using an X-Ray Interferometer in Soft Tissue Tumors

Technology in Cancer Research & Treatment ◽

10.1177/15330338211010121 ◽

2021 ◽

Vol 20 ◽

pp. 153303382110101

Author(s):

Thet-Thet Lwin ◽

Akio Yoneyama ◽

Hiroko Maruyama ◽

Tohoru Takeda

Keyword(s):

Computed Tomography ◽

Soft Tissue ◽

Spatial Resolution ◽

Phase Contrast ◽

Soft Tissue Tumors ◽

X Ray ◽

3 Dimensional ◽

Computed Tomography Images ◽

X Ray Imaging ◽

X Ray Computed

Phase-contrast synchrotron-based X-ray imaging using an X-ray interferometer provides high sensitivity and high spatial resolution, and it has the ability to depict the fine morphological structures of biological soft tissues, including tumors. In this study, we quantitatively compared phase-contrast synchrotron-based X-ray computed tomography images and images of histopathological hematoxylin-eosin-stained sections of spontaneously occurring rat testicular tumors that contained different types of cells. The absolute densities measured on the phase-contrast synchrotron-based X-ray computed tomography images correlated well with the densities of the nuclear chromatin in the histological images, thereby demonstrating the ability of phase-contrast synchrotron-based X-ray imaging using an X-ray interferometer to reliably identify the characteristics of cancer cells within solid soft tissue tumors. In addition, 3-dimensional synchrotron-based phase-contrast X-ray computed tomography enables screening for different structures within tumors, such as solid, cystic, and fibrous tissues, and blood clots, from any direction and with a spatial resolution down to 26 μm. Thus, phase-contrast synchrotron-based X-ray imaging using an X-ray interferometer shows potential for being useful in preclinical cancer research by providing the ability to depict the characteristics of tumor cells and by offering 3-dimensional information capabilities.

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