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Meyer S, Shi SZ, Shapira N, Maidment ADA, Noël PB. Quantitative analysis of speckle-based X-ray dark-field imaging using numerical wave-optics simulations. Sci Rep 2021; 11:16113. [PMID: 34373478 PMCID: PMC8352882 DOI: 10.1038/s41598-021-95227-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 07/12/2021] [Indexed: 11/24/2022] Open
Abstract
The dark-field signal measures the small-angle scattering strength and provides complementary diagnostic information. This is of particular interest for lung imaging due to the pronounced small-angle scatter from the alveolar microstructure. However, most dark-field imaging techniques are relatively complex, dose-inefficient, and require sophisticated optics and highly coherent X-ray sources. Speckle-based imaging promises to overcome these limitations due to its simple and versatile setup, only requiring the addition of a random phase modulator to conventional X-ray equipment. We investigated quantitatively the influence of sample structure, setup geometry, and source energy on the dark-field signal in speckle-based X-ray imaging with wave-optics simulations for ensembles of micro-spheres. We show that the dark-field signal is accurately predicted via a model originally derived for grating interferometry when using the mean frequency of the speckle pattern power spectral density as the characteristic speckle size. The size directly reflects the correlation length of the diffuser surface and did not change with energy or propagation distance within the near-field. The dark-field signal had a distinct dependence on sample structure and setup geometry but was also affected by beam hardening-induced modifications of the visibility spectrum. This study quantitatively demonstrates the behavior of the dark-field signal in speckle-based X-ray imaging.
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Affiliation(s)
- Sebastian Meyer
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19103, USA.
| | - Serena Z Shi
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19103, USA
| | - Nadav Shapira
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19103, USA
| | - Andrew D A Maidment
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19103, USA
| | - Peter B Noël
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19103, USA.
- Department of Diagnostic and Interventional Radiology, School of Medicine and Klinikum rechts der Isar, Technical University of Munich, 81675, Munich, Germany.
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2
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Chalmers MC, Kitchen MJ, Uesugi K, Falzon G, Quin P, Pavlov KM. Tomographic reconstruction using tilted Laue analyser-based X-ray phase-contrast imaging. JOURNAL OF SYNCHROTRON RADIATION 2021; 28:283-291. [PMID: 33399579 DOI: 10.1107/s1600577520013995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 10/20/2020] [Indexed: 06/12/2023]
Abstract
Analyser-based phase-contrast imaging (ABPCI) is a highly sensitive phase-contrast imaging method that produces high-contrast images of weakly absorbing materials. However, it is only sensitive to phase gradient components lying in the diffraction plane of the analyser crystal [i.e. in one dimension (1-D)]. In order to accurately account for and measure phase effects produced by the wavefield-sample interaction, ABPCI and other 1-D phase-sensitive methods must achieve 2-D phase gradient sensitivity. An inclined geometry method was applied to a Laue geometry setup for X-ray ABPCI through rotation of the detector and object about the optical axis. This allowed this traditionally 1-D phase-sensitive phase-contrast method to possess 2-D phase gradient sensitivity. Tomographic datasets were acquired over 360° of a multi-material phantom with the detector and sample tilted by 8°. The real and imaginary parts of the refractive index were reconstructed for the phantom.
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Affiliation(s)
- M C Chalmers
- University of Canterbury, 20 Kirkwood Avenue, Upper Riccarton, Christchurch 8041, New Zealand
| | - M J Kitchen
- Monash University, Wellington Road, Clayton, VIC 3800, Australia
| | - K Uesugi
- Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198, Japan
| | - G Falzon
- College of Science and Engineering, Flinders University, Adelaide, South Australia 5001, Australia
| | - P Quin
- University of New England, Armidale, NSW 2351, Australia
| | - K M Pavlov
- University of Canterbury, 20 Kirkwood Avenue, Upper Riccarton, Christchurch 8041, New Zealand
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3
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Exploring potential of different X-ray imaging methods for early-stage lung cancer detection. RADIATION DETECTION TECHNOLOGY AND METHODS 2020. [DOI: 10.1007/s41605-020-00173-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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4
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Buchanan I, Mittone A, Bravin A, Diemoz P, Endrizzi M, Olivo A. Simplified retrieval method for Edge Illumination X-ray phase contrast imaging allowing multi-modal imaging with fewer input frames. OPTICS EXPRESS 2020; 28:11597-11608. [PMID: 32403667 DOI: 10.1364/oe.372312] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 02/28/2020] [Indexed: 05/23/2023]
Abstract
We present data from an implementation of Edge Illumination (EI) that uses a detector aperture designed for increasing dynamic range, suitable for clinically relevant X-ray energies and demonstrated here using synchrotron radiation. By utilising a sufficiently large crosstalk between pixels, this implementation enables single-scan imaging for phase and absorption, and double-scan for phase, absorption and dark field imaging. The presence of the detector mask enables a direct comparison between conventional EI and beam tracking (BT), which we conduct through Monte Carlo and analytical modelling in the case of a single-scan being used for the retrieval of all three contrasts. In the present case, where the X-ray beam width is comparable to the pixel size, we provide an analysis on best-positioning of the beam on the detector for accurate signal retrieval. Further, we demonstrate an application of this method by distinguishing different concentrations of microbubbles via their dark field signals at high energy using an EI system.
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Zhong Z, Hasnah M, Broadbent A, Dooryhee E, Lucas M. Phase-space matching between bent Laue and flat Bragg crystals. JOURNAL OF SYNCHROTRON RADIATION 2019; 26:1917-1923. [PMID: 31721734 DOI: 10.1107/s1600577519010774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 08/01/2019] [Indexed: 06/10/2023]
Abstract
Through phase-space analysis of Dumond diagrams for a flat Bragg crystal, a single bent Laue crystal and a monochromator consisting of double-bent Laue crystals, this work shows that it is possible to match the flat Bragg crystal to both the single-crystal and double-crystal Laue monochromators. The matched system has the advantage that the phase space of the bent crystal's output beam is much larger than that of the flat crystal, making the combined system stable. Here it is suggested that such a matched system can be used at synchrotron facilities to realize X-ray dark-field imaging, analyzer-based imaging and diffraction-enhanced imaging at beamlines using double-Laue monochromators.
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Affiliation(s)
- Z Zhong
- National Syncrhrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - M Hasnah
- Department of Mathematics, Statistics and Physics, Qatar University, Al Jamiaa Street, Doha, Qatar
| | - A Broadbent
- National Syncrhrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - E Dooryhee
- National Syncrhrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - M Lucas
- National Syncrhrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973, USA
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6
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Wang Z, Liu D, Zhang J, Huang W, Yuan Q, Gao K, Wu Z. Absorption, refraction and scattering retrieval in X-ray analyzer-based imaging. JOURNAL OF SYNCHROTRON RADIATION 2018; 25:1206-1213. [PMID: 29979183 DOI: 10.1107/s1600577518007439] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 05/17/2018] [Indexed: 06/08/2023]
Abstract
A three-image algorithm is proposed in order to retrieve the absorption, refraction and ultra-small-angle X-ray scattering (USAXS) properties of the object in X-ray analyzer-based imaging. Based on the Gaussian fitting to the rocking curve, the novel algorithm is theoretically derived and presented, and validated by synchrotron radiation experiments. Compared with multiple-image radiography, this algorithm only requires a minimum of three intensity measurements, and is therefore advantageous in terms of simplified acquisition procedure and reduced data collection times, which are especially important for specific applications such as in vivo imaging and phase tomography. Moreover, the retrieval algorithm can be specialized to particular cases where some degree of a priori knowledge on the object is available, potentially reducing the minimum number of intensity measurements to two. Furthermore, the effect of angular mis-alignment on the accuracy of the retrieved images was theoretically investigated, which can be of use in image interpretation and optimization of the data acquisition procedure.
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Affiliation(s)
- Zhili Wang
- School of Electronics and Applied Physics, Hefei University of Technology, Hefei, Anhui 230009, People's Republic of China
| | - Dalin Liu
- School of Electronics and Applied Physics, Hefei University of Technology, Hefei, Anhui 230009, People's Republic of China
| | - Jin Zhang
- Institute of High Energy Physics, Chinese Academy of Science, Beijing 100049, People's Republic of China
| | - Wanxia Huang
- Institute of High Energy Physics, Chinese Academy of Science, Beijing 100049, People's Republic of China
| | - Qingxi Yuan
- Institute of High Energy Physics, Chinese Academy of Science, Beijing 100049, People's Republic of China
| | - Kun Gao
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Anhui 230026, People's Republic of China
| | - Zhao Wu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Anhui 230026, People's Republic of China
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7
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Abstract
Advances in cardiovascular computed tomography (CT) have resulted in an excellent ability to exclude coronary heart disease (CHD). Anatomical information, functional information, and spectral information can already be obtained with current CT technologies. Moreover, novel developments such as targeted nanoparticle contrast agents, photon-counting CT, and phase contrast CT will further enhance the diagnostic value of cardiovascular CT. This review provides an overview of current state of the art and future cardiovascular CT imaging.
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Gasilov S, Mittone A, Horng A, Geith T, Bravin A, Baumbach T, Coan P. Hard X-ray index of refraction tomography of a whole rabbit knee joint: A feasibility study. Phys Med 2016; 32:1785-1789. [PMID: 27793538 DOI: 10.1016/j.ejmp.2016.10.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 09/30/2016] [Accepted: 10/01/2016] [Indexed: 10/20/2022] Open
Abstract
We report results of the computed tomography reconstruction of the index of refraction in a whole rabbit knee joint examined at the photon energy of 51keV. Refraction based images make it possible to delineate the bone, cartilage, and soft tissues without adjusting the contrast window width and level. Density variations, which are related to tissue composition and are not visible in absorption X-ray images, are detected in the obtained refraction based images. We discuss why refraction-based images provide better detectability of low contrast features than absorption images.
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Affiliation(s)
- S Gasilov
- Institute for Beam Physics and Technology, Karlsruhe Institute for Technology, Eggenstein 76344, Germany; Department of Physics, Ludwig Maximilians University, Garching 85748, Germany.
| | - A Mittone
- European Synchrotron Radiation Facility, Grenoble 38043, France; Department of Physics, Ludwig Maximilians University, Garching 85748, Germany
| | - A Horng
- Institute for Clinical Radiology, Ludwig-Maximilians-University, Munich 81377, Germany
| | - T Geith
- Institute for Clinical Radiology, Ludwig-Maximilians-University, Munich 81377, Germany
| | - A Bravin
- European Synchrotron Radiation Facility, Grenoble 38043, France
| | - T Baumbach
- Institute for Photon Science and Synchrotron Radiation, Karlsruhe Institute for Technology, Eggenstein 76344, Germany; Laboratory for Application of Synchrotron Radiation, Karlsruhe Institute for Technology, Eggenstein 76344, Germany
| | - P Coan
- Institute for Clinical Radiology, Ludwig-Maximilians-University, Munich 81377, Germany; Department of Physics, Ludwig Maximilians University, Garching 85748, Germany
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Bao Y, Wang Y, Li P, Wu Z, Shao Q, Gao K, Wang Z, Ju Z, Zhang K, Yuan Q, Huang W, Zhu P, Wu Z. A novel crystal-analyzer phase retrieval algorithm and its noise property. JOURNAL OF SYNCHROTRON RADIATION 2015; 22:786-795. [PMID: 25931098 DOI: 10.1107/s1600577515003616] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 02/21/2015] [Indexed: 06/04/2023]
Abstract
A description of the rocking curve in diffraction enhanced imaging (DEI) is presented in terms of the angular signal response function and a simple multi-information retrieval algorithm based on the cosine function fitting. A comprehensive analysis of noise properties of DEI is also given considering the noise transfer characteristic of the X-ray source. The validation has been performed with synchrotron radiation experimental data and Monte Carlo simulations based on the Geant4 toolkit combined with the refractive process of X-rays, which show good agreement with each other. Moreover, results indicate that the signal-to-noise ratios of the refraction and scattering images are about one order of magnitude better than that of the absorption image at the edges of low-Z samples. The noise penalty is drastically reduced with the increasing photon flux and visibility. Finally, this work demonstrates that the analytical method can build an interesting connection between DEI and GDPCI (grating-based differential phase contrast imaging) and is widely suitable for a variety of measurement noise in the angular signal response imaging prototype. The analysis significantly contributes to the understanding of noise characteristics of DEI images and may allow improvements to the signal-to-noise ratio in biomedical and material science imaging.
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Affiliation(s)
- Yuan Bao
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029, People's Republic of China
| | - Yan Wang
- Institute of High Energy Physics, Chinese Academy of Science, Beijing 100049, People's Republic of China
| | - Panyun Li
- Institute of High Energy Physics, Chinese Academy of Science, Beijing 100049, People's Republic of China
| | - Zhao Wu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029, People's Republic of China
| | - Qigang Shao
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029, People's Republic of China
| | - Kun Gao
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029, People's Republic of China
| | - Zhili Wang
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029, People's Republic of China
| | - Zaiqiang Ju
- Institute of High Energy Physics, Chinese Academy of Science, Beijing 100049, People's Republic of China
| | - Kai Zhang
- Institute of High Energy Physics, Chinese Academy of Science, Beijing 100049, People's Republic of China
| | - Qingxi Yuan
- Institute of High Energy Physics, Chinese Academy of Science, Beijing 100049, People's Republic of China
| | - Wanxia Huang
- Institute of High Energy Physics, Chinese Academy of Science, Beijing 100049, People's Republic of China
| | - Peiping Zhu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029, People's Republic of China
| | - Ziyu Wu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029, People's Republic of China
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10
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Majidi K, Li J, Muehleman C, Brankov JG. Noise and analyzer-crystal angular position analysis for analyzer-based phase-contrast imaging. Phys Med Biol 2014; 59:1877-97. [PMID: 24651402 DOI: 10.1088/0031-9155/59/8/1877] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The analyzer-based phase-contrast x-ray imaging (ABI) method is emerging as a potential alternative to conventional radiography. Like many of the modern imaging techniques, ABI is a computed imaging method (meaning that images are calculated from raw data). ABI can simultaneously generate a number of planar parametric images containing information about absorption, refraction, and scattering properties of an object. These images are estimated from raw data acquired by measuring (sampling) the angular intensity profile of the x-ray beam passed through the object at different angular positions of the analyzer crystal. The noise in the estimated ABI parametric images depends upon imaging conditions like the source intensity (flux), measurements angular positions, object properties, and the estimation method. In this paper, we use the Cramér-Rao lower bound (CRLB) to quantify the noise properties in parametric images and to investigate the effect of source intensity, different analyzer-crystal angular positions and object properties on this bound, assuming a fixed radiation dose delivered to an object. The CRLB is the minimum bound for the variance of an unbiased estimator and defines the best noise performance that one can obtain regardless of which estimation method is used to estimate ABI parametric images. The main result of this paper is that the variance (hence the noise) in parametric images is directly proportional to the source intensity and only a limited number of analyzer-crystal angular measurements (eleven for uniform and three for optimal non-uniform) are required to get the best parametric images. The following angular measurements only spread the total dose to the measurements without improving or worsening CRLB, but the added measurements may improve parametric images by reducing estimation bias. Next, using CRLB we evaluate the multiple-image radiography, diffraction enhanced imaging and scatter diffraction enhanced imaging estimation techniques, though the proposed methodology can be used to evaluate any other ABI parametric image estimation technique.
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Affiliation(s)
- Keivan Majidi
- Department of Electrical and Computer Engineering, Illinois Institute of Technology, Chicago, IL 60616, USA
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Munro PRT, Endrizzi M, Diemoz PC, Hagen CK, Szafraniec MB, Millard TP, Zapata CE, Speller RD, Olivo A. Medicine, material science and security: the versatility of the coded-aperture approach. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2014; 372:20130029. [PMID: 24470413 PMCID: PMC3900034 DOI: 10.1098/rsta.2013.0029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The principal limitation to the widespread deployment of X-ray phase imaging in a variety of applications is probably versatility. A versatile X-ray phase imaging system must be able to work with polychromatic and non-microfocus sources (for example, those currently used in medical and industrial applications), have physical dimensions sufficiently large to accommodate samples of interest, be insensitive to environmental disturbances (such as vibrations and temperature variations), require only simple system set-up and maintenance, and be able to perform quantitative imaging. The coded-aperture technique, based upon the edge illumination principle, satisfies each of these criteria. To date, we have applied the technique to mammography, materials science, small-animal imaging, non-destructive testing and security. In this paper, we outline the theory of coded-aperture phase imaging and show an example of how the technique may be applied to imaging samples with a practically important scale.
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Affiliation(s)
- P. R. T. Munro
- Optical and Biomedical Engineering Laboratory, School of Electrical, Electronic and Computer Engineering, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
- Centre for Microscopy, Characterisation and Analysis, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
| | - M. Endrizzi
- Department of Medical Physics and Bioengineering, University College London, Malet Place, Gower St., London WC1E 6BT, UK
| | - P. C. Diemoz
- Department of Medical Physics and Bioengineering, University College London, Malet Place, Gower St., London WC1E 6BT, UK
| | - C. K. Hagen
- Department of Medical Physics and Bioengineering, University College London, Malet Place, Gower St., London WC1E 6BT, UK
| | - M. B. Szafraniec
- Department of Medical Physics and Bioengineering, University College London, Malet Place, Gower St., London WC1E 6BT, UK
| | - T. P. Millard
- Department of Medical Physics and Bioengineering, University College London, Malet Place, Gower St., London WC1E 6BT, UK
| | - C. E. Zapata
- Department of Medical Physics and Bioengineering, University College London, Malet Place, Gower St., London WC1E 6BT, UK
| | - R. D. Speller
- Department of Medical Physics and Bioengineering, University College London, Malet Place, Gower St., London WC1E 6BT, UK
| | - A. Olivo
- Department of Medical Physics and Bioengineering, University College London, Malet Place, Gower St., London WC1E 6BT, UK
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Hetterich H, Willner M, Fill S, Herzen J, Bamberg F, Hipp A, Schüller U, Adam-Neumair S, Wirth S, Reiser M, Pfeiffer F, Saam T. Phase-contrast CT: qualitative and quantitative evaluation of atherosclerotic carotid artery plaque. Radiology 2014; 271:870-8. [PMID: 24588675 DOI: 10.1148/radiol.14131554] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To evaluate the potential of phase-contrast computed tomography (CT) for atherosclerotic plaque imaging in human carotid arteries in an experimental ex vivo study. MATERIALS AND METHODS The study was approved by the institutional review board, and informed consent was obtained from the patients' relatives. Seven postmortem human carotid artery specimens were imaged at a laboratory setup by using a conventional x-ray tube and grating interferometer. After histologic processing, phase-contrast imaging and histopathologic data were matched. Characteristics of the necrotic core (NC) covered by a fibrous cap (FC), intraplaque hemorrhage (IPH), and calcifications (CAs) were established, and sensitivity, specificity, and accuracy of phase-contrast CT for plaque detection and the potential for accurate quantification were assessed. The Cohen κ and Pearson correlation coefficient R were used to determine the agreement between phase-contrast imaging and histopathologic findings for plaque characterization and correlation of quantitative plaque measurements, respectively. A difference with a P value of less than .05 was considered significant. RESULTS Characteristic criteria were found in all analyzed plaque components. Applying these criteria, phase-contrast CT had a good sensitivity for the detection of the FC and NC, IPH, and CAs (all, >80%) and excellent specificity and accuracy (all, >90%), with good interreader agreement (κ ≥ 0.72, P < .0001). There were excellent correlations for quantitative measurements of FC, NC, and CAs between phase-contrast imaging and histopathologic findings (R ≥ 0.92). Interreader reproducibility was excellent, with an intraclass correlation coefficient of 0.98 or higher for all measurements. CONCLUSION The results of this study indicate that ex vivo phase-contrast CT can help identify and quantify atherosclerotic plaque components, with excellent correlation to histopathologic findings. Although not yet applicable in vivo, phase-contrast CT may become a valuable tool to monitor atherosclerotic disease process noninvasively.
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Affiliation(s)
- Holger Hetterich
- From the Institute of Clinical Radiology (H.H., S.F., F.B., S.A., S.W., M.R., T.S.), Center for Neuropathology (U.S.), and Institute of Anatomy (S.A.), Ludwig-Maximilians-University Hospital, Pettenkoferstrasse 8a, 80336 Munich, Germany; {Department of Physics and Institute for Technical Medicine}, Technische Universität München, Garching, Germany (M.W., J.H., A.H., F.P.); and Institute of Materials Research, Helmholtz-Zentrum, Geesthacht, Germany (J.H.)
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Anton G, Bayer F, Beckmann MW, Durst J, Fasching PA, Haas W, Hartmann A, Michel T, Pelzer G, Radicke M, Rauh C, Rieger J, Ritter A, Schulz-Wendtland R, Uder M, Wachter DL, Weber T, Wenkel E, Wucherer L. Grating-based darkfield imaging of human breast tissue. Z Med Phys 2013; 23:228-35. [DOI: 10.1016/j.zemedi.2013.01.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Revised: 12/19/2012] [Accepted: 01/10/2013] [Indexed: 01/21/2023]
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14
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Li J, Sun Y, Zhu P. A theoretically exact reconstruction algorithm for helical cone-beam differential phase-contrast computed tomography. Phys Med Biol 2013; 58:5421-32. [PMID: 23877274 DOI: 10.1088/0031-9155/58/16/5421] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Differential phase-contrast computed tomography (DPC-CT) reconstruction problems are usually solved by using parallel-, fan- or cone-beam algorithms. For rod-shaped objects, the x-ray beams cannot recover all the slices of the sample at the same time. Thus, if a rod-shaped sample is required to be reconstructed by the above algorithms, one should alternately perform translation and rotation on this sample, which leads to lower efficiency. The helical cone-beam CT may significantly improve scanning efficiency for rod-shaped objects over other algorithms. In this paper, we propose a theoretically exact filter-backprojection algorithm for helical cone-beam DPC-CT, which can be applied to reconstruct the refractive index decrement distribution of the samples directly from two-dimensional differential phase-contrast images. Numerical simulations are conducted to verify the proposed algorithm. Our work provides a potential solution for inspecting the rod-shaped samples using DPC-CT, which may be applicable with the evolution of DPC-CT equipments.
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Affiliation(s)
- Jing Li
- School of Information and Communication Engineering, Dalian University of Technology, Dalian, Liaoning Province 116023, People's Republic of China.
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15
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Munro PRT, Hagen CK, Szafraniec MB, Olivo A. A simplified approach to quantitative coded aperture X-ray phase imaging. OPTICS EXPRESS 2013; 21:11187-201. [PMID: 23669976 DOI: 10.1364/oe.21.011187] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We recently demonstrated how quantitative X-ray phase contrast imaging may be performed with laboratory sources using the coded aperture technique. This technique required the knowledge of system parameters such as, for example, the source focal spot size and distances between elements of the imaging system. The method also assumes that the absorbing regions of the apertures are perfectly absorbing. In this paper we demonstrate how quantitative imaging can be performed without knowledge of individual system parameters and with partially absorbing apertures. We also show that this method is analogous to that employed in analyser based imaging which uses the rocking curve of an analyser crystal.
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Affiliation(s)
- Peter R T Munro
- Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic and Computer Engineering, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia.
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16
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Munro PRT, Rigon L, Ignatyev K, Lopez FCM, Dreossi D, Speller RD, Olivo A. A quantitative, non-interferometric X-ray phase contrast imaging technique. OPTICS EXPRESS 2013; 21:647-61. [PMID: 23388958 PMCID: PMC3696730 DOI: 10.1364/oe.21.000647] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
We present a quantitative, non-interferometric, X-ray differential phase contrast imaging technique based on the edge illumination principle. We derive a novel phase retrieval algorithm which requires only two images to be acquired and verify the technique experimentally using synchrotron radiation. The technique is useful for planar imaging but is expected to be important for quantitative phase tomography also. The properties and limitations of the technique are studied in detail.
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Affiliation(s)
- Peter R T Munro
- Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic and Computer Engineering, The University of Western Australia, Crawley, Western Australia 6009, Australia.
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Bravin A, Coan P, Suortti P. X-ray phase-contrast imaging: from pre-clinical applications towards clinics. Phys Med Biol 2012; 58:R1-35. [PMID: 23220766 DOI: 10.1088/0031-9155/58/1/r1] [Citation(s) in RCA: 379] [Impact Index Per Article: 31.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Phase-contrast x-ray imaging (PCI) is an innovative method that is sensitive to the refraction of the x-rays in matter. PCI is particularly adapted to visualize weakly absorbing details like those often encountered in biology and medicine. In past years, PCI has become one of the most used imaging methods in laboratory and preclinical studies: its unique characteristics allow high contrast 3D visualization of thick and complex samples even at high spatial resolution. Applications have covered a wide range of pathologies and organs, and are more and more often performed in vivo. Several techniques are now available to exploit and visualize the phase-contrast: propagation- and analyzer-based, crystal and grating interferometry and non-interferometric methods like the coded aperture. In this review, covering the last five years, we will give an overview of the main theoretical and experimental developments and of the important steps performed towards the clinical implementation of PCI.
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Affiliation(s)
- Alberto Bravin
- European Synchrotron Radiation Facility, 6 rue Horowitz, 38043 Grenoble Cedex, France.
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Sztrókay A, Diemoz PC, Schlossbauer T, Brun E, Bamberg F, Mayr D, Reiser MF, Bravin A, Coan P. High-resolution breast tomography at high energy: a feasibility study of phase contrast imaging on a whole breast. Phys Med Biol 2012; 57:2931-42. [PMID: 22516937 DOI: 10.1088/0031-9155/57/10/2931] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Previous studies on phase contrast imaging (PCI) mammography have demonstrated an enhancement of breast morphology and cancerous tissue visualization compared to conventional imaging. We show here the first results of the PCI analyser-based imaging (ABI) in computed tomography (CT) mode on whole and large (>12 cm) tumour-bearing breast tissues. We demonstrate in this work the capability of the technique of working at high x-ray energies and producing high-contrast images of large and complex specimens. One entire breast of an 80-year-old woman with invasive ductal cancer was imaged using ABI-CT with monochromatic 70 keV x-rays and an area detector of 92×92 µm² pixel size. Sagittal slices were reconstructed from the acquired data, and compared to corresponding histological sections. Comparison with conventional absorption-based CT was also performed. Five blinded radiologists quantitatively evaluated the visual aspects of the ABI-CT images with respect to sharpness, soft tissue contrast, tissue boundaries and the discrimination of different structures/tissues. ABI-CT excellently depicted the entire 3D architecture of the breast volume by providing high-resolution and high-contrast images of the normal and cancerous breast tissues. These results are an important step in the evolution of PCI-CT towards its clinical implementation.
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Affiliation(s)
- A Sztrókay
- Institute of Clinical Radiology, Ludwig-Maximilians University, Munich, Germany
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Li J, Zhu P, Sun Y. An approximate reconstruction method for helical cone-beam differential phase-contrast computed tomography images. Phys Med Biol 2012; 57:2347-56. [DOI: 10.1088/0031-9157/57/8/2347] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Modregger P, Pinzer BR, Thüring T, Rutishauser S, David C, Stampanoni M. Sensitivity of X-ray grating interferometry. OPTICS EXPRESS 2011; 19:18324-38. [PMID: 21935201 DOI: 10.1364/oe.19.018324] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
It is known that the sensitivity of X-ray phase-contrast grating interferometry with regard to electron density variations present in the sample is related to the minimum detectable refraction angle. In this article a numerical framework is developed that allows for a realistic and quantitative determination of the sensitivity. The framework is validated by comparisons with experimental results and then used for the quantification of several influences on the sensitivity, such as spatial coherence or the number of phase step images. In particular, we identify the ideal inter-grating distance with respect to the highest sensitivity for parallel beam geometry. This knowledge will help to optimize existing synchrotron-based grating interferometry setups.
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Affiliation(s)
- P Modregger
- Swiss Light Source, Paul Scherrer Institut, Villigen, Switzerland.
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Diemoz PC, Bravin A, Glaser C, Coan P. Comparison of analyzer-based imaging computed tomography extraction algorithms and application to bone-cartilage imaging. Phys Med Biol 2010; 55:7663-79. [DOI: 10.1088/0031-9155/55/24/018] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Coan P, Wagner A, Bravin A, Diemoz PC, Keyriläinen J, Mollenhauer J. In vivo x-ray phase contrast analyzer-based imaging for longitudinal osteoarthritis studies in guinea pigs. Phys Med Biol 2010; 55:7649-62. [PMID: 21113092 DOI: 10.1088/0031-9155/55/24/017] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Over the last two decades phase contrast x-ray imaging techniques have been extensively studied for applications in the biomedical field. Published results demonstrate the high capability of these imaging modalities of improving the image contrast of biological samples with respect to standard absorption-based radiography and routinely used clinical imaging techniques. A clear depiction of the anatomic structures and a more accurate disease diagnosis may be provided by using radiation doses comparable to or lower than those used in current clinical methods. In the literature many works show images of phantoms and excised biological samples proving the high sensitivity of the phase contrast imaging methods for in vitro investigations. In this scenario, the applications of the so-called analyzer-based x-ray imaging (ABI) phase contrast technique are particularly noteworthy. The objective of this work is to demonstrate the feasibility of in vivo x-ray ABI phase contrast imaging for biomedical applications and in particular with respect to joint anatomic depiction and osteoarthritis detection. ABI in planar and tomographic modes was performed in vivo on articular joints of guinea pigs in order to investigate the animals with respect to osteoarthritis by using highly monochromatic x-rays of 52 keV and a low noise detector with a pixel size of 47 × 47 µm(2). Images give strong evidence of the ability of ABI in depicting both anatomic structures in complex systems as living organisms and all known signs of osteoarthritis with high contrast, high spatial resolution and with an acceptable radiation dose. This paper presents the first proof of principle study of in vivo application of ABI. The technical challenges encountered when imaging an animal in vivo are discussed. This experimental study is an important step toward the study of clinical applications of phase contrast x-ray imaging techniques.
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Affiliation(s)
- Paola Coan
- Faculty of Medicine and Institute of Clinical Radiology, Ludwig-Maximilians University, Munich, Germany.
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Kitchen MJ, Paganin DM, Uesugi K, Allison BJ, Lewis RA, Hooper SB, Pavlov KM. X-ray phase, absorption and scatter retrieval using two or more phase contrast images. OPTICS EXPRESS 2010; 18:19994-20012. [PMID: 20940891 DOI: 10.1364/oe.18.019994] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We have developed two phase-retrieval techniques for analyser-based phase contrast imaging that provide information about an object's X-ray absorption, refraction and scattering properties. The first requires rocking curves to be measured with and without the sample and improves upon existing techniques by accurately fitting the curves with Pearson type VII functions. The second employs an iterative approach using two simultaneously recorded images by exploiting the Laue crystal geometry. This technique provides a substantial reduction in X-ray dose and enables quantitative phase retrieval to be performed on images of moving objects.
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Characterization of Osteoarthritic and Normal Human Patella Cartilage by Computed Tomography X-ray Phase-Contrast Imaging. Invest Radiol 2010; 45:437-44. [DOI: 10.1097/rli.0b013e3181e193bd] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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