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Partridge T, Wolfson P, Jiang J, Massimi L, Astolfo A, Djurabekova N, Savvidis S, Jones CJM, Hagen CK, Millard E, Shorrock W, Waltham RM, Haig IG, Bate D, Ho KMA, Mc Bain H, Wilson A, Hogan A, Delaney H, Liyadipita A, Levine AP, Dawas K, Mohammadi B, Qureshi YA, Chouhan MD, Taylor SA, Mughal M, Munro PRT, Endrizzi M, Novelli M, Lovat LB, Olivo A. T staging esophageal tumors with x rays. OPTICA 2024; 11:569-576. [PMID: 39006164 PMCID: PMC11239146 DOI: 10.1364/optica.501948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 03/05/2024] [Accepted: 04/07/2024] [Indexed: 07/16/2024]
Abstract
With histopathology results typically taking several days, the ability to stage tumors during interventions could provide a step change in various cancer interventions. X-ray technology has advanced significantly in recent years with the introduction of phase-based imaging methods. These have been adapted for use in standard labs rather than specialized facilities such as synchrotrons, and approaches that enable fast 3D scans with conventional x-ray sources have been developed. This opens the possibility to produce 3D images with enhanced soft tissue contrast at a level of detail comparable to histopathology, in times sufficiently short to be compatible with use during surgical interventions. In this paper we discuss the application of one such approach to human esophagi obtained from esophagectomy interventions. We demonstrate that the image quality is sufficiently high to enable tumor T staging based on the x-ray datasets alone. Alongside detection of involved margins with potentially life-saving implications, staging tumors intra-operatively has the potential to change patient pathways, facilitating optimization of therapeutic interventions during the procedure itself. Besides a prospective intra-operative use, the availability of high-quality 3D images of entire esophageal tumors can support histopathological characterization, from enabling "right slice first time" approaches to understanding the histopathology in the full 3D context of the surrounding tumor environment.
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Affiliation(s)
- T. Partridge
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, UK
| | - P. Wolfson
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, UK
- Division of Surgery and Interventional Science, UCL, London WC1E 6BT, UK
| | - J. Jiang
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, UK
- Current address: Advanced Photon Source, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - L. Massimi
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, UK
| | - A. Astolfo
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, UK
- Nikon X-Tek Systems Ltd., Tring, Herts HP23 4JX, UK
| | - N. Djurabekova
- Department of Computer Science, UCL, London WC1E 6BT, UK
| | - S. Savvidis
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, UK
| | - C. J. Maughan Jones
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, UK
| | - C. K. Hagen
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, UK
| | - E. Millard
- Nikon X-Tek Systems Ltd., Tring, Herts HP23 4JX, UK
| | - W. Shorrock
- Nikon X-Tek Systems Ltd., Tring, Herts HP23 4JX, UK
| | | | - I. G. Haig
- Nikon X-Tek Systems Ltd., Tring, Herts HP23 4JX, UK
| | - D. Bate
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, UK
- Nikon X-Tek Systems Ltd., Tring, Herts HP23 4JX, UK
| | - K. M. A. Ho
- Division of Surgery and Interventional Science, UCL, London WC1E 6BT, UK
| | - H. Mc Bain
- Division of Surgery and Interventional Science, UCL, London WC1E 6BT, UK
| | - A. Wilson
- Division of Surgery and Interventional Science, UCL, London WC1E 6BT, UK
| | - A. Hogan
- Division of Surgery and Interventional Science, UCL, London WC1E 6BT, UK
| | - H. Delaney
- Department of Histopathology, UCL, London WC1E 6BT, UK
| | - A. Liyadipita
- Department of Histopathology, UCL, London WC1E 6BT, UK
| | - A. P. Levine
- Department of Histopathology, UCL, London WC1E 6BT, UK
| | - K. Dawas
- Department of Upper Gastro-Intestinal Surgery, UCLH, London NW1 2BU, UK
| | - B. Mohammadi
- Department of Upper Gastro-Intestinal Surgery, UCLH, London NW1 2BU, UK
| | - Y. A. Qureshi
- Department of Upper Gastro-Intestinal Surgery, UCLH, London NW1 2BU, UK
| | - M. D. Chouhan
- Center for Medical Imaging, Division of Medicine, UCL, London WC1E 6BT, UK
- Princess Alexandra Hospital Medical Imaging Department, Brisbane, Queensland, Australia
- University of Queensland Medical School, Saint Lucia, Queensland, Australia
| | - S. A. Taylor
- Center for Medical Imaging, Division of Medicine, UCL, London WC1E 6BT, UK
| | - M. Mughal
- Department of Upper Gastro-Intestinal Surgery, UCLH, London NW1 2BU, UK
| | - P. R. T. Munro
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, UK
| | - M. Endrizzi
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, UK
| | - M. Novelli
- Research Department of Pathology, Cancer Institute, UCLH, London NW1 2BU, UK
| | - L. B. Lovat
- Division of Surgery and Interventional Science, UCL, London WC1E 6BT, UK
| | - A. Olivo
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, UK
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Massimi L, Suaris T, Hagen CK, Endrizzi M, Munro PRT, Havariyoun G, Hawker PMS, Smit B, Astolfo A, Larkin OJ, Waltham RM, Shah Z, Duffy SW, Nelan RL, Peel A, Jones JL, Haig IG, Bate D, Olivo A. Volumetric High-Resolution X-Ray Phase-Contrast Virtual Histology of Breast Specimens With a Compact Laboratory System. IEEE TRANSACTIONS ON MEDICAL IMAGING 2022; 41:1188-1195. [PMID: 34941505 PMCID: PMC7612751 DOI: 10.1109/tmi.2021.3137964] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The assessment of margin involvement is a fundamental task in breast conserving surgery to prevent recurrences and reoperations. It is usually performed through histology, which makes the process time consuming and can prevent the complete volumetric analysis of large specimens. X-ray phase contrast tomography combines high resolution, sufficient penetration depth and high soft tissue contrast, and can therefore provide a potential solution to this problem. In this work, we used a high-resolution implementation of the edge illumination X-ray phase contrast tomography based on "pixel-skipping" X-ray masks and sample dithering, to provide high definition virtual slices of breast specimens. The scanner was originally designed for intra-operative applications in which short scanning times were prioritised over spatial resolution; however, thanks to the versatility of edge illumination, high-resolution capabilities can be obtained with the same system simply by swapping x-ray masks without this imposing a reduction in the available field of view. This makes possible an improved visibility of fine tissue strands, enabling a direct comparison of selected CT slices with histology, and providing a tool to identify suspect features in large specimens before slicing. Combined with our previous results on fast specimen scanning, this works paves the way for the design of a multi-resolution EI scanner providing intra-operative capabilities as well as serving as a digital pathology system.
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Astolfo A, Buchanan I, Partridge T, Kallon GK, Hagen CK, Munro PRT, Endrizzi M, Bate D, Olivo A. The effect of a variable focal spot size on the contrast channels retrieved in edge-illumination X-ray phase contrast imaging. Sci Rep 2022; 12:3354. [PMID: 35233022 PMCID: PMC8888612 DOI: 10.1038/s41598-022-07376-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 02/01/2022] [Indexed: 11/09/2022] Open
Abstract
Multi-modal X-ray imaging allows the extraction of phase and dark-field (or “Ultra-small Angle Scatter”) images alongside conventional attenuation ones. Recently, scan-based systems using conventional sources that can simultaneously output the above three images on relatively large-size objects have been developed by various groups. One limitation is the need for some degree of spatial coherence, achieved either through the use of microfocal sources, or by placing an absorption grating in front of an extended source. Both these solutions limit the amount of flux available for imaging, with the latter also leading to a more complex setup with additional alignment requirements. Edge-illumination partly overcomes this as it was proven to work with focal spots of up to 100 micron. While high-flux, 100 micron focal spot sources do exist, their comparatively large footprint and high cost can be obstacles to widespread translation. A simple solution consists in placing a single slit in front of a large focal spot source. We used a tunable slit to study the system performance at various effective focal spot sizes, by extracting transmission, phase and dark-field images of the same specimens for a range of slit widths. We show that consistent, repeatable results are obtained for varying X-ray statistics and effective focal spot sizes. As the slit width is increased, the expected reduction in the raw differential phase peaks is observed, compensated for in the retrieval process by a broadened sensitivity function. This leads to the same values being correctly retrieved, but with a slightly larger error bar i.e. a reduction in phase sensitivity. Concurrently, a slight increase in the dark-field signal is also observed.
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Affiliation(s)
- A Astolfo
- Nikon X-Tek Systems Ltd, Tring, Herts, HP23 4JX, UK.,Department of Medical Physics and Biomedical Engineering, UCL, London, WC1E 6BT, UK
| | - I Buchanan
- Department of Medical Physics and Biomedical Engineering, UCL, London, WC1E 6BT, UK
| | - T Partridge
- Department of Medical Physics and Biomedical Engineering, UCL, London, WC1E 6BT, UK
| | - G K Kallon
- Department of Medical Physics and Biomedical Engineering, UCL, London, WC1E 6BT, UK
| | - C K Hagen
- Department of Medical Physics and Biomedical Engineering, UCL, London, WC1E 6BT, UK
| | - P R T Munro
- Department of Medical Physics and Biomedical Engineering, UCL, London, WC1E 6BT, UK
| | - M Endrizzi
- Department of Medical Physics and Biomedical Engineering, UCL, London, WC1E 6BT, UK
| | - D Bate
- Nikon X-Tek Systems Ltd, Tring, Herts, HP23 4JX, UK.,Department of Medical Physics and Biomedical Engineering, UCL, London, WC1E 6BT, UK
| | - A Olivo
- Department of Medical Physics and Biomedical Engineering, UCL, London, WC1E 6BT, UK.
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Piovesan A, Vancauwenberghe V, Van De Looverbosch T, Verboven P, Nicolaï B. X-ray computed tomography for 3D plant imaging. TRENDS IN PLANT SCIENCE 2021; 26:1171-1185. [PMID: 34404587 DOI: 10.1016/j.tplants.2021.07.010] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 07/05/2021] [Accepted: 07/21/2021] [Indexed: 06/13/2023]
Abstract
X-ray computed tomography (CT) is a valuable tool for 3D imaging of plant tissues and organs. Applications include the study of plant development and organ morphogenesis, as well as modeling of transport processes in plants. Some challenges remain, however, including attaining higher contrast for easier quantification, increasing the resolution for imaging subcellular features, and decreasing image acquisition and processing time for high-throughput phenotyping. In addition, phase contrast, multispectral, dark-field, soft X-ray, and time-resolved imaging are emerging. At the same time, a large amount of 3D image data are becoming available, posing challenges for data management. We review recent advances in the area of X-ray CT for plant imaging, and describe opportunities for using such images for studying transport processes in plants.
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Affiliation(s)
- Agnese Piovesan
- Katholieke Universiteit (KU) Leuven, Division MeBioS (Mechatronics, Biostatistics, and Sensors) - Postharvest Group, Willem de Croylaan 42, BE-3001 Leuven, Belgium
| | - Valérie Vancauwenberghe
- Katholieke Universiteit (KU) Leuven, Division MeBioS (Mechatronics, Biostatistics, and Sensors) - Postharvest Group, Willem de Croylaan 42, BE-3001 Leuven, Belgium
| | - Tim Van De Looverbosch
- Katholieke Universiteit (KU) Leuven, Division MeBioS (Mechatronics, Biostatistics, and Sensors) - Postharvest Group, Willem de Croylaan 42, BE-3001 Leuven, Belgium
| | - Pieter Verboven
- Katholieke Universiteit (KU) Leuven, Division MeBioS (Mechatronics, Biostatistics, and Sensors) - Postharvest Group, Willem de Croylaan 42, BE-3001 Leuven, Belgium.
| | - Bart Nicolaï
- Katholieke Universiteit (KU) Leuven, Division MeBioS (Mechatronics, Biostatistics, and Sensors) - Postharvest Group, Willem de Croylaan 42, BE-3001 Leuven, Belgium; Flanders Centre of Postharvest Technology (VCBT), Willem de Croylaan 42, BE-3001 Leuven, Belgium
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Massimi L, Partridge T, Astolfo A, Endrizzi M, Hagen CK, Munro PRT, Bate D, Olivo A. Optimization of multipoint phase retrieval in edge illumination X-ray imaging: A theoretical and experimental analysis. Med Phys 2021; 48:5884-5896. [PMID: 34387879 DOI: 10.1002/mp.15162] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Revised: 07/11/2021] [Accepted: 08/03/2021] [Indexed: 11/09/2022] Open
Abstract
PURPOSE In this work, an analytical model describing the noise in the retrieved three contrast channels, transmission, refraction, and ultra small-angle scattering, obtained with edge illumination X-ray phase-based imaging system is presented and compared to experimental data. METHODS In EI, images acquired at different displacements of the presample mask (i.e., different illumination levels referred to as points on the "illumination curve"), followed by pixel-wise curve fitting, are exploited to quantitatively retrieve the three contrast channels. Therefore, the noise in the final image will depend on the error associated with the fitting process. We use a model based on the derivation of the standard error on fitted parameters, which relies on the calculation of the covariance matrix, to estimate the noise and the cross-channel correlation as a function of the position of the sampling points. In particular, we investigated the most common cases of 3 and 5 sampling points. In addition, simulations have been used to better understand the role of the integration time for each sampling point. Finally, the model is validated by comparison with the experimental data acquired with an edge illumination setup based on a tungsten rotating anode X-ray source and a photon counting detector. RESULTS We found a good match between the predictions of the model and the experimental data. In particular, for the investigated cases, an arrangement of the sampling points leading to minimum noise and cross-channel correlation can be found. Simulations revealed that, given a fixed overall scanning time, its distribution into the smallest possible number of sampling points needed for phase retrieval leads to minimum noise thanks to higher statistics per point. CONCLUSIONS This work presents an analytical model describing the noise in the various contrast channels retrieved in edge illumination as a function of the illumination curve sampling. In particular, an optimal sampling scheme leading to minimum noise has been determined for the case where 3 or 5 sampling points are used, which represent two of the most common acquisition schemes. In addition, the correlation between noise in the different channels and the role of the number of points and exposure time have been also investigated. In general, our results suggest a series of procedures that should be followed in order to optimize the experimental acquisitions.
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Affiliation(s)
- Lorenzo Massimi
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK
| | - Tom Partridge
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK
| | - Alberto Astolfo
- Nikon X-Tek Systems Ltd., Tring Business Centre, Tring, Hertfordshire, UK
| | - Marco Endrizzi
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK
| | - Charlotte K Hagen
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK
| | - Peter R T Munro
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK
| | - David Bate
- Nikon X-Tek Systems Ltd., Tring Business Centre, Tring, Hertfordshire, UK
| | - Alessandro Olivo
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK
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Zhao Y, Zhao Q, Zheng M, Yang T, Liu D, Sun L, Lv W, Li Y, Liu Y, Hu C. Comparison of microstructural imaging of the root canal isthmus using propagation-based X-ray phase-contrast and absorption micro-computed tomography. J Microsc 2021; 284:74-82. [PMID: 34143441 DOI: 10.1111/jmi.13042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Revised: 06/04/2021] [Accepted: 06/16/2021] [Indexed: 11/30/2022]
Abstract
Clear and complete microstructural imaging of the root canal isthmus is an important part of pathological investigations in research and clinical practice. X-ray micro-computed tomography (μCT) is a widely used non-destructive imaging technique, which allows for distortion-free three-dimensional (3D) visualisation. While absorption μCT typically has poor contrast resolution for observing the root canal isthmus, especially for weak-absorbing tissues, propagation-based X-ray phase-contrast imaging (PBI) is a powerful imaging method, which in its combination with μCT (PB-PCμCT) enables high-resolution and high-contrast microstructural imaging of the weak-absorbing tissues in samples. To investigate the feasibility and ability of PB-PCμCT in microstructural imaging of the root canal isthmus, conventional absorption μCT and PB-PCμCT experiments were performed. The two-dimensional (2D) and 3D comparison results demonstrated that, compared to absorption μCT, PB-PCμCT has the ability to image the root canal isthmus more clearly and completely, and thus, it has great potential to serve as a valuable tool for biomedical and preclinical studies on the root canal isthmus.
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Affiliation(s)
- Yuqing Zhao
- School of Biomedical Engineering and Technology, Tianjin Medical University, Tianjin, People's Republic of China
| | - Qi Zhao
- School of Biomedical Engineering and Technology, Tianjin Medical University, Tianjin, People's Republic of China
| | - Mengting Zheng
- School of Biomedical Engineering and Technology, Tianjin Medical University, Tianjin, People's Republic of China
| | - Tingting Yang
- School of Biomedical Engineering and Technology, Tianjin Medical University, Tianjin, People's Republic of China
| | - Dayong Liu
- Tianjin Medical University School of Stomatology, Tianjin, People's Republic of China
| | - Lianlian Sun
- Department of Stomatology, Fifth Central of Tianjin, Tianjin, People's Republic of China
| | - Wenjuan Lv
- School of Biomedical Engineering and Technology, Tianjin Medical University, Tianjin, People's Republic of China
| | - Yimin Li
- School of Biomedical Engineering and Technology, Tianjin Medical University, Tianjin, People's Republic of China
| | - Yongchao Liu
- Department of Radiation Oncology, Fifth Central of Tianjin, Tianjin, People's Republic of China
| | - Chunhong Hu
- School of Biomedical Engineering and Technology, Tianjin Medical University, Tianjin, People's Republic of China
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Hagen CK, Endrizzi M, Towns R, Meganck JA, Olivo A. A Preliminary Investigation into the Use of Edge Illumination X-ray Phase Contrast Micro-CT for Preclinical Imaging. Mol Imaging Biol 2021; 22:539-548. [PMID: 31250331 PMCID: PMC7250795 DOI: 10.1007/s11307-019-01396-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Purpose To enable a preliminary assessment of the suitability of edge illumination (EI) x-ray phase contrast (XPC) micro x-ray computed tomography (micro-CT) to preclinical imaging. Specifically, to understand how different acquisition schemes and their combination with dedicated data processing affect contrast-to-noise ratio (CNR) and spatial resolution, while providing control over scan time and radiation dose delivery. Procedures Deceased mice (n = 3) were scanned with an EI XPC micro-CT setup operated under different settings, leading to scan times between 18 h and 13 min. For the shortest scan, the entrance dose was measured with a calibrated PTW 23344 ion chamber. Different data processing methods were applied, retrieving either separate attenuation and phase images, or hybrid (combined attenuation and phase) images. A quantitative comparison was performed based on CNR and spatial resolution measurements for a soft tissue interface. Results All phase-based images have led to a higher CNR for the considered soft tissue interface than the attenuation image, independent of scan time. The best relative CNR (a sixfold increase) was observed in one of the hybrid images. Spatial resolution was found to be connected to scan time, with a resolution of approximately 20 μm and 60 μm achieved for the longest and shortest scans, respectively. An entrance dose of approximately 300 mGy was estimated for the scan performed within 13 min. Conclusions Despite their preliminary nature, our results suggest that EI XPC bears potential for enhancing the utility of preclinical micro-CT, and, pending further research and development, could ultimately become a valuable technique in this field.
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Affiliation(s)
- Charlotte K Hagen
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London, WC1E 6BT, UK.
| | - Marco Endrizzi
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London, WC1E 6BT, UK
| | - Rebecca Towns
- Biological Services, University College London, Gower Street, London, WC1E 6BT, UK
| | - Jeffrey A Meganck
- Research and Development, Life Sciences Technology, PerkinElmer, 68 Elm St, Hopkinton, MA, 01748, USA
| | - Alessandro Olivo
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London, WC1E 6BT, UK
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Birnbacher L, Braig EM, Pfeiffer D, Pfeiffer F, Herzen J. Quantitative X-ray phase contrast computed tomography with grating interferometry : Biomedical applications of quantitative X-ray grating-based phase contrast computed tomography. Eur J Nucl Med Mol Imaging 2021; 48:4171-4188. [PMID: 33846846 PMCID: PMC8566444 DOI: 10.1007/s00259-021-05259-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 02/11/2021] [Indexed: 11/25/2022]
Abstract
The ability of biomedical imaging data to be of quantitative nature is getting increasingly important with the ongoing developments in data science. In contrast to conventional attenuation-based X-ray imaging, grating-based phase contrast computed tomography (GBPC-CT) is a phase contrast micro-CT imaging technique that can provide high soft tissue contrast at high spatial resolution. While there is a variety of different phase contrast imaging techniques, GBPC-CT can be applied with laboratory X-ray sources and enables quantitative determination of electron density and effective atomic number. In this review article, we present quantitative GBPC-CT with the focus on biomedical applications.
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Affiliation(s)
- Lorenz Birnbacher
- Physics Department, Munich School of Bioengineering, Technical University of Munich, Munich, Germany
- Department of Diagnostic and Interventional Radiology, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Eva-Maria Braig
- Physics Department, Munich School of Bioengineering, Technical University of Munich, Munich, Germany
| | - Daniela Pfeiffer
- Department of Diagnostic and Interventional Radiology, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Franz Pfeiffer
- Physics Department, Munich School of Bioengineering, Technical University of Munich, Munich, Germany
- Department of Diagnostic and Interventional Radiology, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Julia Herzen
- Physics Department, Munich School of Bioengineering, Technical University of Munich, Munich, Germany.
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Massimi L, Buchanan I, Astolfo A, Endrizzi M, Olivo A. Fast, non-iterative algorithm for quantitative integration of X-ray differential phase-contrast images. OPTICS EXPRESS 2020; 28:39677-39687. [PMID: 33379512 DOI: 10.1364/oe.405755] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 11/18/2020] [Indexed: 05/23/2023]
Abstract
X-ray phase contrast imaging is gaining importance as an imaging tool. However, it is common for X-ray phase detection techniques to be sensitive to the derivatives of the phase. Therefore, the integration of differential phase images is a fundamental step both to access quantitative pixel content and for further analysis such as segmentation. The integration of noisy data leads to artefacts with a severe impact on image quality and on its quantitative content. In this work, an integration method based on the Wiener filter is presented and tested using simulated and real data obtained with the edge illumination differential X-ray phase imaging method. The method is shown to provide high image quality while preserving the quantitative pixel content of the integrated image. In addition, it requires a short computational time making it suitable for large datasets.
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Massimi L, Meganck JA, Towns R, Olivo A, Endrizzi M. Evaluation of a compact multicontrast and multiresolution X-ray phase contrast edge illumination system for small animal imaging. Med Phys 2020; 48:376-386. [PMID: 33107980 DOI: 10.1002/mp.14553] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 10/13/2020] [Accepted: 10/18/2020] [Indexed: 01/20/2023] Open
Abstract
PURPOSE In this work the performance of a compact multiresolution and multicontrast x-ray phase system based on edge illumination is investigated. It has been designed for small animal imaging and with a limited footprint for ease of deployment in laboratories. METHODS The presented edge illumination system is based on a compact microfocus tungsten x-ray source combined with a flat panel detector. The source has a maximum output of 10 W when the minimum spot size of about 15 μm is used. The system has an overall length of 70 cm. A new double sample mask design, obtained by arranging both skipped and nonskipped configurations on the same structure, provides dual resolution capability. To test the system, we carried out computed tomography (CT) scans of a plastic phantom with different source settings using both single-image and multi-image acquisition schemes at different spatial resolutions. In addition, CT scans of an ex-vivo mouse specimen were acquired at the best identified working conditions to demonstrate the application of the presented system to small animal imaging. RESULTS We found this system delivers good image quality, allowing for an efficient material separation and improving detail visibility in small animals thanks to the higher signal-to-noise ratio (SNR) of phase contrast with respect to conventional attenuation contrast. The system offers high versatility in terms of spatial resolution thanks to the double sample mask design integrated into a single scanner. The availability of both multi- and single-image acquisition schemes coupled with their dedicated retrieval algorithms, allows different working modes which can be selected based on user preference. Multi-image acquisition provides quantitative separation of the real and imaginary part of the refractive index, however, it requires a long scanning time. On the other hand, the single image approach delivers the best material separation and image quality at all the investigated source settings with a shorter scanning time but at the cost of quantitativeness. Finally, we also observed that the single image approach combined with a high-power x-ray source may result in a fast acquisition protocol compatible with in-vivo imaging.
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Affiliation(s)
- Lorenzo Massimi
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London, WC1E 6BT, UK
| | - Jeffrey A Meganck
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London, WC1E 6BT, UK.,Research and Development, Life Sciences Technology, PerkinElmer, Hopkinton, MA, USA
| | - Rebecca Towns
- Biological Services, University College London, Gower Street, London, WC1E 6BT, UK
| | - Alessandro Olivo
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London, WC1E 6BT, UK
| | - Marco Endrizzi
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London, WC1E 6BT, UK
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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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12
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Modregger P, Meganck J, Hagen CK, Massimi L, Olivo A, Endrizzi M. Improved iterative tomographic reconstruction for x-ray imaging with edge-illumination. Phys Med Biol 2019; 64:205008. [PMID: 31509810 DOI: 10.1088/1361-6560/ab439d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Iterative tomographic reconstruction has been established as a viable alternative for data analysis in phase-sensitive x-ray imaging based on the edge-illumination principle. However, previously published approaches did not account for drifts of optical elements during a scan, which can lead to artefacts. Up to now, the strategy to reduce these artefacts was to acquire additional intermediate flat field images, which were used to correct the sinograms. Here, we expand the theoretical model to take these effects into account and demonstrate a significant reduction of (ring)-artefacts in the final reconstructions, while allowing for a significant reduction of scan time and dose. We further improve the model by including the capability to reconstruct combined absorption and phase contrast slices, which we experimentally demonstrate to deliver improved contrast to noise ratios compared to previously employed single shot approaches.
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Affiliation(s)
- Peter Modregger
- Department of Medical Physics and Bioengineering, University College London, Gower Street, WC1E 6BT London, United Kingdom. Author to whom correspondence should be addressed
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13
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Hosono R, Kawabata T, Hayashida K, Kudo T, Ozaki K, Teranishi N, Hatsui T, Hosoi T, Watanabe H, Shimura T. Advancement of X-ray radiography using microfocus X-ray source in conjunction with amplitude grating and SOI pixel detector, SOPHIAS. OPTICS EXPRESS 2018; 26:21044-21053. [PMID: 30119410 DOI: 10.1364/oe.26.021044] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 07/25/2018] [Indexed: 06/08/2023]
Abstract
We show how to improve microfocus X-ray radiography by using the SOPHIAS silicon-on-insulator pixel detector in conjunction with an amplitude grating. Single-exposure multi-energy absorption and differential phase contrast imaging was performed using the single amplitude grating method. The sensitivity in differential phase contrast imaging in a two-pixel-pitch setup was enhanced by 39% in comparison with the previously reported method [Rev. Sci. Instrum. 81, 113702 (2010).] by analyzing charge-sharing effects. Small-angle-scattering imaging was also possible in the two-pixel-pitch setup by counting the number of X-ray photons passing the pixel boundaries.
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14
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Single-Shot X-ray Phase Retrieval through Hierarchical Data Analysis and a Multi-Aperture Analyser. J Imaging 2018. [DOI: 10.3390/jimaging4060076] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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15
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Zamir A, Hagen C, Diemoz PC, Endrizzi M, Vittoria F, Chen Y, Anastasio MA, Olivo A. Recent advances in edge illumination x-ray phase-contrast tomography. J Med Imaging (Bellingham) 2017; 4:040901. [PMID: 29057286 PMCID: PMC5641577 DOI: 10.1117/1.jmi.4.4.040901] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 09/21/2017] [Indexed: 11/14/2022] Open
Abstract
Edge illumination (EI) is an x-ray phase-contrast imaging technique, exploiting sensitivity to x-ray refraction to visualize features, which are often not detected by conventional absorption-based radiography. The method does not require a high degree of spatial coherence and is achromatic and, therefore, can be implemented with both synchrotron radiation and commercial x-ray tubes. Using different retrieval algorithms, information about an object's attenuation, refraction, and scattering properties can be obtained. In recent years, a theoretical framework has been developed that enables EI computed tomography (CT) and, hence, three-dimensional imaging. This review provides a summary of these advances, covering the development of different image acquisition schemes, retrieval approaches, and applications. These developments constitute an integral part in the transformation of EI CT into a widely spread imaging tool for use in a range of fields.
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Affiliation(s)
- Anna Zamir
- University College London, Department of Medical Physics and Biomedical Engineering, London, United Kingdom
| | - Charlotte Hagen
- University College London, Department of Medical Physics and Biomedical Engineering, London, United Kingdom
| | - Paul C Diemoz
- University College London, Department of Medical Physics and Biomedical Engineering, London, United Kingdom
| | - Marco Endrizzi
- University College London, Department of Medical Physics and Biomedical Engineering, London, United Kingdom
| | - Fabio Vittoria
- University College London, Department of Medical Physics and Biomedical Engineering, London, United Kingdom
| | - Yujia Chen
- Washington University in St. Louis, Department of Biomedical Engineering, St. Louis, Missouri, United States
| | - Mark A Anastasio
- Washington University in St. Louis, Department of Biomedical Engineering, St. Louis, Missouri, United States
| | - Alessandro Olivo
- University College London, Department of Medical Physics and Biomedical Engineering, London, United Kingdom
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16
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Hybrid framework for feasible modeling of an edge illumination X-ray phase-contrast imaging system at a human scale. Phys Med 2017; 40:1-10. [PMID: 28729133 DOI: 10.1016/j.ejmp.2017.05.067] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 05/21/2017] [Accepted: 05/24/2017] [Indexed: 11/24/2022] Open
Abstract
Here, we present a hybrid approach for simulating an edge illumination X-ray phase-contrast imaging (EIXPCi) set-up using graphics processor units (GPU) with a high degree of accuracy. In this study, the applicability of pixel, mesh and non-uniform rational B-splines (NURBS) objects to carry out realistic maps of X-ray phase-contrast distribution at a human scale is accounted for by using numerical anthropomorphic phantoms and a very fast and robust simulation framework which integrates total interaction probabilities along selected X-ray paths. We exploit the mathematical and algorithmic properties of NURBS and describe how to represent human scale phantoms in an edge illumination X-ray phase-contrast model. The presented implementation allows the modeling of a variety of physical interactions of x-rays with different mathematically described objects and the recording of quantities, e.g. path integrals, interaction sites and deposited energies. Furthermore, our efficient, scalable and optimized hybrid Monte Carlo and ray-tracing projector can be used in iterative reconstruction algorithms on multi GPU heterogeneous systems. The preliminary results of our innovative approach show the fine performance of an edge illumination X-ray phase-contrast medical imaging system on various human-like soft tissues with noticeably reduced computation time. Our approach to the EIXPCi modeling confirms that building a true imaging system at a human scale should be possible and the simulations presented here aim at its future development.
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17
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Modregger P, Kagias M, Irvine SC, Brönnimann R, Jefimovs K, Endrizzi M, Olivo A. Interpretation and Utility of the Moments of Small-Angle X-Ray Scattering Distributions. PHYSICAL REVIEW LETTERS 2017; 118:265501. [PMID: 28707948 DOI: 10.1103/physrevlett.118.265501] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Indexed: 05/23/2023]
Abstract
Small angle x-ray scattering has been proven to be a valuable method for accessing structural information below the spatial resolution limit implied by direct imaging. Here, we theoretically derive the relation that links the subpixel differential phase signal provided by the sample to the moments of scattering distributions accessible by refraction sensitive x-ray imaging techniques. As an important special case we explain the scatter or dark-field contrast in terms of the sample's phase signal. Further, we establish that, for binary phase objects, the nth moment scales with the difference of the refractive index decrement to the power of n. Finally, we experimentally demonstrate the utility of the moments by quantitatively determining the particle sizes of a range of powders with a laboratory-based setup.
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Affiliation(s)
- Peter Modregger
- Department of Medical Physics and Bioengineering, University College London, Gower Street, WC1E 6BT London, United Kingdom
| | - Matias Kagias
- Swiss Light Source, Paul Scherrer Institut, 5232 Villigen, Switzerland
- Institute for Biomedical Engineering, UZH/ETH Zürich, 8092 Zürich, Switzerland
| | - Sarah C Irvine
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, OX11 0DE Oxfordshire, United Kingdom
| | - Rolf Brönnimann
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Reliability Science and Technology, Überlandstrasse 129, 8600 Dübendorf, Switzerland
| | - Konstantins Jefimovs
- Swiss Light Source, Paul Scherrer Institut, 5232 Villigen, Switzerland
- Institute for Biomedical Engineering, UZH/ETH Zürich, 8092 Zürich, Switzerland
| | - Marco Endrizzi
- Department of Medical Physics and Bioengineering, University College London, Gower Street, WC1E 6BT London, United Kingdom
| | - Alessandro Olivo
- Department of Medical Physics and Bioengineering, University College London, Gower Street, WC1E 6BT London, United Kingdom
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18
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Endrizzi M, Vittoria FA, Rigon L, Dreossi D, Iacoviello F, Shearing PR, Olivo A. X-ray Phase-Contrast Radiography and Tomography with a Multiaperture Analyzer. PHYSICAL REVIEW LETTERS 2017; 118:243902. [PMID: 28665636 DOI: 10.1103/physrevlett.118.243902] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Indexed: 05/23/2023]
Abstract
We present a multiaperture analyzer setup for performing x-ray phase contrast imaging in planar and three-dimensional modalities. The method is based on strongly structuring the x-ray beam with an amplitude modulator, before it reaches the sample, and on a multiaperture analyzing element before detection. A multislice representation of the sample is used to establish a quantitative relation between projection images and the corresponding three-dimensional distributions, leading to successful tomographic reconstruction. Sample absorption, phase, and scattering are retrieved from the measurement of five intensity projections. The method is tested on custom-built phantoms with synchrotron radiation: sample absorption and phase can be reliably retrieved also in combination with strong scatterers, simultaneously attaining high sensitivity and dynamic range.
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Affiliation(s)
- M Endrizzi
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - F A Vittoria
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - L Rigon
- Physics Department, University of Trieste, Via Valerio 2, 34127 Trieste, Italy
- Istituto Nazionale di Fisica Nulceare, Sezione di Trieste, Via Valerio 2, 34127 Trieste, Italy
| | - D Dreossi
- Sincrotrone Trieste SCpA, S.S. 14 km 163.5, 34012 Basovizza Trieste, Italy
| | - F Iacoviello
- Electrochemical Innovation Lab, Department of Chemical Engineering, University College London, WC1E 7JE, United Kingdom
| | - P R Shearing
- Electrochemical Innovation Lab, Department of Chemical Engineering, University College London, WC1E 7JE, United Kingdom
| | - A Olivo
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London WC1E 6BT, United Kingdom
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19
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Zamir A, Diemoz PC, Vittoria FA, Hagen CK, Endrizzi M, Olivo A. Edge illumination X-ray phase tomography of multi-material samples using a single-image phase retrieval algorithm. OPTICS EXPRESS 2017; 25:11984-11996. [PMID: 28788753 DOI: 10.1364/oe.25.011984] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In this paper we present a single-image phase retrieval algorithm for multi-material samples, developed for the edge illumination (EI) X-ray phase contrast imaging method. The theoretical derivation is provided, along with any assumptions made. The algorithm is evaluated quantitatively using both simulated and experimental results from a computed tomography (CT) scan using the EI laboratory implementation. Qualitative CT results are provided for a biological sample containing both bone and soft-tissue. Using a single EI image per projection and knowledge of the complex refractive index, the algorithm can accurately retrieve the interface between a given pair of materials. A composite CT slice can be created by splicing together multiple CT reconstructions, each retrieved for a different pair of materials.
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20
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Diémoz PC, Vittoria FA, Hagen CK, Endrizzi M, Coan P, Bravin A, Wagner UH, Rau C, Robinson IK, Olivo A. A single-image retrieval method for edge illumination X-ray phase-contrast imaging: Application and noise analysis. Phys Med 2016; 32:1759-1764. [DOI: 10.1016/j.ejmp.2016.07.093] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 07/11/2016] [Accepted: 07/19/2016] [Indexed: 11/28/2022] Open
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21
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Diemoz PC, Bravin A, Sztrókay-Gaul A, Ruat M, Grandl S, Mayr D, Auweter S, Mittone A, Brun E, Ponchut C, Reiser MF, Coan P, Olivo A. A method for high-energy, low-dose mammography using edge illumination x-ray phase-contrast imaging. Phys Med Biol 2016; 61:8750-8761. [PMID: 27893445 DOI: 10.1088/1361-6560/61/24/8750] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Since the breast is one of the most radiosensitive organs, mammography is arguably the area where lowering radiation dose is of the uttermost importance. Phase-based x-ray imaging methods can provide opportunities in this sense, since they do not require x-rays to be stopped in tissue for image contrast to be generated. Therefore, x-ray energy can be considerably increased compared to those usually exploited by conventional mammography. In this article we show how a novel, optimized approach can lead to considerable dose reductions. This was achieved by matching the edge-illumination phase method, which reaches very high angular sensitivity also at high x-ray energies, to an appropriate image processing algorithm and to a virtually noise-free detection technology capable of reaching almost 100% efficiency at the same energies. Importantly, while proof-of-concept was obtained at a synchrotron, the method has potential for a translation to conventional sources.
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Affiliation(s)
- Paul C Diemoz
- Department of Medical Physics and Biomedical Engineering, University College London, London, WC1E 6BT, UK
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22
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Modregger P, Cremona TP, Benarafa C, Schittny JC, Olivo A, Endrizzi M. Small angle x-ray scattering with edge-illumination. Sci Rep 2016; 6:30940. [PMID: 27491917 PMCID: PMC4974648 DOI: 10.1038/srep30940] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Accepted: 07/11/2016] [Indexed: 11/24/2022] Open
Abstract
Sensitivity to sub-pixel sample features has been demonstrated as a valuable capability of phase contrast x-ray imaging. Here, we report on a method to obtain angular-resolved small angle x-ray scattering distributions with edge-illumination- based imaging utilizing incoherent illumination from an x-ray tube. Our approach provides both the three established image modalities (absorption, differential phase and scatter strength), plus a number of additional contrasts related to unresolved sample features. The complementarity of these contrasts is experimentally validated by using different materials in powder form. As a significant application example we show that the extended complementary contrasts could allow the diagnosis of pulmonary emphysema in a murine model. In support of this, we demonstrate that the properties of the retrieved scattering distributions are consistent with the expectation of increased feature sizes related to pulmonary emphysema. Combined with the simplicity of implementation of edge-illumination, these findings suggest a high potential for exploiting extended sub-pixel contrasts in the diagnosis of lung diseases and beyond.
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Affiliation(s)
- Peter Modregger
- Department of Medical Physics and Bioengineering, University College London, Gower Street, WC1E 6BT London, United Kingdom
| | - Tiziana P. Cremona
- Institute of Anatomy, University of Berne, Baltzerstrasse 2, 3012 Bern, Switzerland
| | - Charaf Benarafa
- Theodor Kocher Institute, University of Berne, Freiestrasse 1, 3012 Bern, Switzerland
| | - Johannes C. Schittny
- Institute of Anatomy, University of Berne, Baltzerstrasse 2, 3012 Bern, Switzerland
| | - Alessandro Olivo
- Department of Medical Physics and Bioengineering, University College London, Gower Street, WC1E 6BT London, United Kingdom
| | - Marco Endrizzi
- Department of Medical Physics and Bioengineering, University College London, Gower Street, WC1E 6BT London, United Kingdom
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23
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Asymmetric masks for laboratory-based X-ray phase-contrast imaging with edge illumination. Sci Rep 2016; 6:25466. [PMID: 27145924 PMCID: PMC4857105 DOI: 10.1038/srep25466] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 04/18/2016] [Indexed: 02/08/2023] Open
Abstract
We report on an asymmetric mask concept that enables X-ray phase-contrast imaging without requiring any movement in the system during data acquisition. The method is compatible with laboratory equipment, namely a commercial detector and a rotating anode tube. The only motion required is that of the object under investigation which is scanned through the imaging system. Two proof-of-principle optical elements were designed, fabricated and experimentally tested. Quantitative measurements on samples of known shape and composition were compared to theory with good agreement. The method is capable of measuring the attenuation, refraction and (ultra-small-angle) X-ray scattering, does not have coherence requirements and naturally adapts to all those situations in which the X-ray image is obtained by scanning a sample through the imaging system.
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24
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Vittoria FA, Endrizzi M, Diemoz PC, Zamir A, Wagner UH, Rau C, Robinson IK, Olivo A. X-ray absorption, phase and dark-field tomography through a beam tracking approach. Sci Rep 2015; 5:16318. [PMID: 26541117 PMCID: PMC4635357 DOI: 10.1038/srep16318] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 10/12/2015] [Indexed: 11/09/2022] Open
Abstract
We present a development of the beam-tracking approach that allows its implementation in computed tomography. One absorbing mask placed before the sample and a high resolution detector are used to track variations in the beam intensity distribution caused by the sample. Absorption, refraction, and dark-field are retrieved through a multi-Gaussian interpolation of the beam. Standard filtered back projection is used to reconstruct three dimensional maps of the real and imaginary part of the refractive index, and of the dark-field signal. While the method is here demonstrated using synchrotron radiation, its low coherence requirements suggest a possible implementation with laboratory sources.
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Affiliation(s)
- Fabio A Vittoria
- Department of Medical Physics and Biomedical Engineering, University College London, Malet Place, Gower Street, WC1E 6BT London, United Kingdom.,Research Complex at Harwell, Harwell Oxford Campus, OX11 0FA Didcot, United Kingdom
| | - Marco Endrizzi
- Department of Medical Physics and Biomedical Engineering, University College London, Malet Place, Gower Street, WC1E 6BT London, United Kingdom
| | - Paul C Diemoz
- Department of Medical Physics and Biomedical Engineering, University College London, Malet Place, Gower Street, WC1E 6BT London, United Kingdom.,Research Complex at Harwell, Harwell Oxford Campus, OX11 0FA Didcot, United Kingdom
| | - Anna Zamir
- Department of Medical Physics and Biomedical Engineering, University College London, Malet Place, Gower Street, WC1E 6BT London, United Kingdom
| | - Ulrich H Wagner
- Diamond Light Source, Harwell Oxford Campus, OX11 0DE Didcot, United Kingdom
| | - Christoph Rau
- Diamond Light Source, Harwell Oxford Campus, OX11 0DE Didcot, United Kingdom
| | - Ian K Robinson
- Research Complex at Harwell, Harwell Oxford Campus, OX11 0FA Didcot, United Kingdom.,London Centre for Nanotechnology, WC1H 0AH London, United Kingdom
| | - Alessandro Olivo
- Department of Medical Physics and Biomedical Engineering, University College London, Malet Place, Gower Street, WC1E 6BT London, United Kingdom
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