scholarly journals X-ray Phase-Contrast Computed Tomography for Soft Tissue Imaging at the Imaging and Medical Beamline (IMBL) of the Australian Synchrotron

2021 ◽  
Vol 11 (9) ◽  
pp. 4120
Author(s):  
Benedicta D. Arhatari ◽  
Andrew W. Stevenson ◽  
Brian Abbey ◽  
Yakov I. Nesterets ◽  
Anton Maksimenko ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Soft Tissue ◽  
Medical Imaging ◽  
Breast Imaging ◽  
Phase Contrast ◽  
Phase Retrieval ◽  
Short Exposure ◽  
X Rays ◽  
Ongoing Research ◽  
X Ray

The Imaging and Medical Beamline (IMBL) is a superconducting multipole wiggler-based beamline at the 3 GeV Australian Synchrotron operated by the Australian Nuclear Science and Technology Organisation (ANSTO). The beamline delivers hard X-rays in the 25–120 keV energy range and offers the potential for a range of biomedical X-ray applications, including radiotherapy and medical imaging experiments. One of the imaging modalities available at IMBL is propagation-based X-ray phase-contrast computed tomography (PCT). PCT produces superior results when imaging low-density materials such as soft tissue (e.g., breast mastectomies) and has the potential to be developed into a valuable medical imaging tool. We anticipate that PCT will be utilized for medical breast imaging in the near future with the advantage that it could provide better contrast than conventional X-ray absorption imaging. The unique properties of synchrotron X-ray sources such as high coherence, energy tunability, and high brightness are particularly well-suited for generating PCT data using very short exposure times on the order of less than 1 min. The coherence of synchrotron radiation allows for phase-contrast imaging with superior sensitivity to small differences in soft-tissue density. Here we also compare the results of PCT using two different detectors, as these unique source characteristics need to be complemented with a highly efficient detector. Moreover, the application of phase retrieval for PCT image reconstruction enables the use of noisier images, potentially significantly reducing the total dose received by patients during acquisition. This work is part of ongoing research into innovative tomographic methods aimed at the introduction of 3D X-ray medical imaging at the IMBL to improve the detection and diagnosis of breast cancer. Major progress in this area at the IMBL includes the characterization of a large number of mastectomy samples, both normal and cancerous, which have been scanned at clinically acceptable radiation dose levels and evaluated by expert radiologists with respect to both image quality and cancer diagnosis.

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

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.

scholarly journals Robust phase retrieval for high resolution edge illumination x-ray phase-contrast computed tomography in non-ideal environments

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Anna Zamir ◽  
Marco Endrizzi ◽  
Charlotte K. Hagen ◽  
Fabio A. Vittoria ◽  
Luca Urbani ◽  
...  
Keyword(s):  
Computed Tomography ◽  
High Resolution ◽  
Phase Contrast ◽  
Phase Retrieval ◽  
X Ray

scholarly journals Functionalized synchrotron in-line phase-contrast computed tomography: a novel approach for simultaneous quantification of structural alterations and localization of barium-labelled alveolar macrophages within mouse lung samples

2015 ◽  
Vol 22 (1) ◽  
pp. 143-155 ◽  
Author(s):  
Christian Dullin ◽  
Simeone dal Monego ◽  
Emanuel Larsson ◽  
Sara Mohammadi ◽  
Martin Krenkel ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Lung Tissue ◽  
Alveolar Macrophages ◽  
Phase Contrast ◽  
Phase Retrieval ◽  
Cell Tracking ◽  
Structural Changes ◽  
Mouse Lung ◽  
X Ray ◽  
Novel Approach

Functionalized computed tomography (CT) in combination with labelled cells is virtually non-existent due to the limited sensitivity of X-ray-absorption-based imaging, but would be highly desirable to realise cell tracking studies in entire organisms. In this study we applied in-line free propagation X-ray phase-contrast CT (XPCT) in an allergic asthma mouse model to assess structural changes as well as the biodistribution of barium-labelled macrophages in lung tissue. Alveolar macrophages that were barium-sulfate-loaded and fluorescent-labelled were instilled intratracheally into asthmatic and control mice. Mice were sacrificed after 24 h, lungs were keptin situ, inflated with air and scanned utilizing XPCT at the SYRMEP beamline (Elettra Synchrotron Light Source, Italy). Single-distance phase retrieval was used to generate data sets with ten times greater contrast-to-noise ratio than absorption-based CT (in our setup), thus allowing to depict and quantify structural hallmarks of asthmatic lungs such as reduced air volume, obstruction of airways and increased soft-tissue content. Furthermore, we found a higher concentration as well as a specific accumulation of the barium-labelled macrophages in asthmatic lung tissue. It is believe that XPCT will be beneficial in preclinical asthma research for both the assessment of therapeutic response as well as the analysis of the role of the recruitment of macrophages to inflammatory sites.

scholarly journals Detection of involved margins in breast specimens with X-ray phase-contrast computed tomography

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Lorenzo Massimi ◽  
Tamara Suaris ◽  
Charlotte K. Hagen ◽  
Marco Endrizzi ◽  
Peter R. T. Munro ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Phase Contrast ◽  
Histological Analysis ◽  
Breast Conserving Surgery ◽  
X Rays ◽  
Contrast Imaging ◽  
X Ray ◽  
Margin Involvement ◽  
Tissue Sensitivity ◽  
Higher Sensitivity

AbstractMargins of wide local excisions in breast conserving surgery are tested through histology, which can delay results by days and lead to second operations. Detection of margin involvement intraoperatively would allow the removal of additional tissue during the same intervention. X-ray phase contrast imaging (XPCI) provides soft tissue sensitivity superior to conventional X-rays: we propose its use to detect margin involvement intraoperatively. We have developed a system that can perform phase-based computed tomography (CT) scans in minutes, used it to image 101 specimens approximately half of which contained neoplastic lesions, and compared results against those of a commercial system. Histological analysis was carried out on all specimens and used as the gold standard. XPCI-CT showed higher sensitivity (83%, 95% CI 69–92%) than conventional specimen imaging (32%, 95% CI 20–49%) for detection of lesions at margin, and comparable specificity (83%, 95% CI 70–92% vs 86%, 95% CI 73–93%). Within the limits of this study, in particular that specimens obtained from surplus tissue typically contain small lesions which makes detection more difficult for both methods, we believe it likely that the observed increase in sensitivity will lead to a comparable reduction in the number of re-operations.

scholarly journals Quantitative X-ray phase contrast waveguide imaging of bacterial endospores

2015 ◽  
Vol 48 (2) ◽  
pp. 464-476 ◽  
Author(s):  
R. N. Wilke ◽  
M. Hoppert ◽  
M. Krenkel ◽  
M. Bartels ◽  
T. Salditt
Keyword(s):  
Phase Contrast ◽  
Phase Retrieval ◽  
Mass Density ◽  
Field Of View ◽  
Large Field ◽  
Single Individual ◽  
X Rays ◽  
Contrast Imaging ◽  
X Ray ◽  
Freeze Dried

Quantitative waveguide-based X-ray phase contrast imaging has been carried out on the level of single, unstained, unsliced and freeze-dried bacterial cells ofBacillus thuringiensisandBacillus subtilisusing hard X-rays of 7.9 keV photon energy. The cells have been prepared in the metabolically dormant state of an endospore. The quantitative phase maps obtained by iterative phase retrieval using a modified hybrid input–output algorithm allow for mass and mass density determinations on the level of single individual endospores but include also large field of view investigations. Additionally, a direct reconstruction based on the contrast transfer function is investigated, and the two approaches are compared. Depending on the field of view and method, a resolution down to 65 nm was achieved at a maximum applied dose of below 5 × 105 Gy. Masses in the range of about ∼110–190 (20) fg for isolated endospores have been obtained.

Potential of propagation-based synchrotron X-ray phase-contrast computed tomography for cardiac tissue engineering

2017 ◽  
Vol 24 (4) ◽  
pp. 842-853 ◽  
Author(s):  
Mohammad Izadifar ◽  
Paul Babyn ◽  
Dean Chapman ◽  
Michael E. Kelly ◽  
Xiongbiao Chen
Keyword(s):  
Computed Tomography ◽  
Tissue Engineering ◽  
Soft Tissue ◽  
Ct Scan ◽  
Phase Contrast ◽  
Cardiac Tissue ◽  
Cardiac Tissue Engineering ◽  
X Ray ◽  
Imaging Quality ◽  
Scan Time

Hydrogel-based cardiac tissue engineering offers great promise for myocardial infarction repair. The ability to visualize engineered systemsin vivoin animal models is desired to monitor the performance of cardiac constructs. However, due to the low density and weak X-ray attenuation of hydrogels, conventional radiography and micro-computed tomography are unable to visualize the hydrogel cardiac constructs upon their implantation, thus limiting their use in animal systems. This paper presents a study on the optimization of synchrotron X-ray propagation-based phase-contrast imaging computed tomography (PCI-CT) for three-dimensional (3D) visualization and assessment of the hydrogel cardiac patches. First, alginate hydrogel was 3D-printed into cardiac patches, with the pores filled by fibrin. The hydrogel patches were then surgically implanted on rat hearts. A week after surgery, the hearts including patches were excised and embedded in a soft-tissue-mimicking gel for imaging by using PCI-CT at an X-ray energy of 25 keV. During imaging, the sample-to-detector distances, CT-scan time and the region of interest (ROI) were varied and examined for their effects on both imaging quality and radiation dose. The results showed that phase-retrieved PCI-CT images provided edge-enhancement fringes at a sample-to-detector distance of 147 cm that enabled visualization of anatomical and microstructural features of the myocardium and the implanted patch in the tissue-mimicking gel. For visualization of these features, PCI-CT offered a significantly higher performance than the dual absorption-phase and clinical magnetic resonance (3 T) imaging techniques. Furthermore, by reducing the total CT-scan time and ROI, PCI-CT was examined for lowering the effective dose, meanwhile without much loss of imaging quality. In effect, the higher soft tissue contrast and low-dose potential of PCI-CT has been used along with an acceptable overall animal dose to achieve the high spatial resolution needed for cardiac implant visualization. As a result, PCI-CT at the identified imaging parameters offers great potential for 3D assessment of microstructural features of hydrogel cardiac patches.

scholarly journals Phase-contrast computed tomography for quantification of structural changes in lungs of asthma mouse models of different severity

2015 ◽  
Vol 22 (4) ◽  
pp. 1106-1111 ◽  
Author(s):  
Christian Dullin ◽  
Emanuel Larsson ◽  
Giuliana Tromba ◽  
Andrea M. Markus ◽  
Frauke Alves
Keyword(s):  
Computed Tomography ◽  
Soft Tissue ◽  
Mouse Models ◽  
Phase Contrast ◽  
Phase Retrieval ◽  
Airway Disease ◽  
High Porosity ◽  
Lung Structure ◽  
Contrast Ct ◽  
Free Propagation

Lung imaging in mouse disease models is crucial for the assessment of the severity of airway disease but remains challenging due to the small size and the high porosity of the organ. Synchrotron inline free-propagation phase-contrast computed tomography (CT) with its intrinsic high soft-tissue contrast provides the necessary sensitivity and spatial resolution to analyse the mouse lung structure in great detail. Here, this technique has been applied in combination with single-distance phase retrieval to quantify alterations of the lung structure in experimental asthma mouse models of different severity. In order to mimic anin vivosituation as close as possible, the lungs were inflated with air at a constant physiological pressure. Entire mice were embedded in agarose gel and imaged using inline free-propagation phase-contrast CT at the SYRMEP beamline (Synchrotron Light Source, `Elettra', Trieste, Italy). The quantification of the obtained phase-contrast CT data sets revealed an increasing lung soft-tissue content in mice correlating with the degree of the severity of experimental allergic airways disease. In this way, it was possible to successfully discriminate between healthy controls and mice with either mild or severe allergic airway disease. It is believed that this approach may have the potential to evaluate the efficacy of novel therapeutic strategies that target airway remodelling processes in asthma.

Phase-Contrast Tomographic Imaging Using an X-ray Interferometer

1998 ◽  
Vol 5 (3) ◽  
pp. 309-314 ◽  
Author(s):  
Atsushi Momose ◽  
Tohoru Takeda ◽  
Yuji Itai ◽  
Akio Yoneyama ◽  
Keiichi Hirano
Keyword(s):  
Phase Contrast ◽  
Phase Retrieval ◽  
X Rays ◽  
Contrast Imaging ◽  
X Ray ◽  
Tomographic Image Reconstruction ◽  
X Ray Computed ◽  
Preliminary Study ◽  
Breast Tissues

Apparatus for phase-contrast X-ray computed tomography using a monolithic X-ray interferometer is presented with some observational results for human breast tissues. Structures characteristic of the tissues were revealed in the phase-contrast tomograms. The procedure of image analysis consists of phase retrieval from X-ray interference patterns and tomographic image reconstruction from the retrieved phase shift. Next, feasibility of phase-contrast imaging using a two-crystal X-ray interferometer was studied aiming at in vivo observation in the future. In a preliminary study, the two-crystal X-ray interferometer was capable of generating fringes of 70% visibility using synchrotron X-rays.

A Radiologist's Art in CT Images

2013 ◽  
Vol 3 (4) ◽  
pp. 61-66
Author(s):  
Piyu Deo Mahant
Keyword(s):  
Computed Tomography ◽  
Medical Imaging ◽  
Human Body ◽  
Ct Images ◽  
Ct Scans ◽  
X Rays ◽  
Imaging Studies ◽  
X Ray ◽  
X Ray Computed

The story of medical imaging starts on 8 Nov, 1895, when Wilhelm Conrad Röntgen accidentally discovered X rays. Since then it has undergone great technological advancements helping physicians create images of the human body to reveal, diagnose, or examine disease (X-ray, n.d). CT scans combine the use of computers and x-rays to create virtual 'slices' of what is inside our body without cutting it open. Earlier many diseases could only be confirmed at autopsy. In 2010, more than 5 billion medical imaging studies were completed done worldwide (X-ray computed tomography, n.d).

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