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Abstract
Ever since the discovery of X-rays, tremendous efforts have been made to develop new imaging techniques for unlocking the hidden secrets of our world and enriching our understanding of it. X-ray differential phase contrast imaging, which measures the gradient of a sample's phase shift, can reveal more detail in a weakly absorbing sample than conventional absorption contrast. However, normally only the gradient's component in two mutually orthogonal directions is measurable. In this article, omnidirectional differential phase images, which record the gradient of phase shifts in all directions of the imaging plane, are efficiently generated by scanning an easily obtainable, randomly structured modulator along a spiral path. The retrieved amplitude and main orientation images for differential phase yield more information than the existing imaging methods. Importantly, the omnidirectional dark-field images can be simultaneously extracted to study strongly ordered scattering structures. The proposed method can open up new possibilities for studying a wide range of complicated samples composed of both heavy, strongly scattering atoms and light, weakly scattering atoms.
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Recent advances in X-ray imaging of breast tissue: From two- to three-dimensional imaging. Phys Med 2020; 79:69-79. [PMID: 33171371 DOI: 10.1016/j.ejmp.2020.10.025] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2020] [Revised: 10/13/2020] [Accepted: 10/24/2020] [Indexed: 11/20/2022] Open
Abstract
Breast cancer is a globally widespread disease whose detection has already been significantly improved by the introduction of screening programs. Nevertheless, mammography suffers from low soft tissue contrast and the superposition of diagnostically relevant anatomical structures as well as from low values for sensitivity and specificity especially for dense breast tissue. In recent years, two techniques for X-ray breast imaging have been developed that bring advances for the early detection of breast cancer. Grating-based phase-contrast mammography is a new imaging technique that is able to provide three image modalities simultaneously (absorption-contrast, phase-contrast and dark-field signal). Thus, an enhanced detection and delineation of cancerous structures in the phase-contrast image and an improved visualization and characterization of microcalcifications in the dark-field image is possible. Furthermore, latest studies about this approach show that dose-compatible imaging with polychromatic X-ray sources is feasible. In order to additionally overcome the limitations of projection-based imaging, efforts were also made towards the development of breast computed tomography (BCT), which recently led to the first clinical installation of an absorption-based BCT system. Further research combining the benefits of both imaging technologies is currently in progress. This review article summarizes the latest advances in phase-contrast imaging for the female breast (projection-based and three-dimensional view) with special focus on possible clinical implementations in the future.
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Zhang R, Fowler AM, Wilke LG, Kelcz F, Garrett JW, Chen GH, Li K. Fast acquisition with seamless stage translation (FASST) for a trimodal x-ray breast imaging system. Med Phys 2020; 47:4356-4362. [PMID: 32458449 PMCID: PMC7704901 DOI: 10.1002/mp.14297] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 04/08/2020] [Accepted: 05/19/2020] [Indexed: 12/16/2022] Open
Abstract
PURPOSE A major technical obstacle to bringing x-ray multicontrast (i.e., attenuation, phase, and dark-field) imaging methodology to clinical use is the prolonged data acquisition time caused by the phase stepping procedure. The purpose of this work was to introduce a fast acquisition with seamless stage translation (FASST) technique to a prototype multicontrast breast imaging system for reduced image acquisition time that is clinically acceptable. METHODS The prototype system was constructed based on a Hologic full-field digital mammography + digital breast tomosynthesis combination system. During each FASST acquisition process, a motorized stage holding a diffraction grating travels continuously with a constant velocity, and a train of 15 short x-ray pulses (35 ms each) was delivered by using the Zero-Degree Tomo mode of the Hologic system. Standard phase retrieval was applied to the 15 subimages without spatial interpolation to avoid spatial resolution loss. The method was evaluated using a physical phantom, a bovine udder specimen, and a freshly resected mastectomy specimen. The FASST technique was experimentally compared with single-shot acquisition methods and the standard phase stepping method. RESULTS The image acquisition time of the proposed method is 3.7 s. In comparison, conventional phase stepping took 105 s using the same prototype imaging system. The mean glandular dose of both methods was matched at 1.3 mGy. No artifacts or spatial resolution loss was observed in images produced by FASST. In contrast, the single-shot methods led to spatial resolution loss and residual moiré artifacts. CONCLUSIONS The FASST technique reduces the data acquisition time of the prototype multicontrast x-ray breast imaging system to 3.7 s, such that it is comparable to a clinical digital breast tomosynthesis exam.
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Affiliation(s)
- Ran Zhang
- Department of Medical Physics, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, WI, 53705, USA
| | - Amy M Fowler
- Department of Radiology, University of Wisconsin-Madison, 600 Highland Avenue, Madison, WI, 53792, USA
- University of Wisconsin Carbone Cancer Center, 600 Highland Avenue, Madison, WI, 53792, USA
| | - Lee G Wilke
- University of Wisconsin Carbone Cancer Center, 600 Highland Avenue, Madison, WI, 53792, USA
- Department of Surgery, Clinical Science Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53792, USA
| | - Frederick Kelcz
- Department of Radiology, University of Wisconsin-Madison, 600 Highland Avenue, Madison, WI, 53792, USA
| | - John W Garrett
- Department of Radiology, University of Wisconsin-Madison, 600 Highland Avenue, Madison, WI, 53792, USA
| | - Guang-Hong Chen
- Department of Medical Physics, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, WI, 53705, USA
- Department of Radiology, University of Wisconsin-Madison, 600 Highland Avenue, Madison, WI, 53792, USA
| | - Ke Li
- Department of Medical Physics, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, WI, 53705, USA
- Department of Radiology, University of Wisconsin-Madison, 600 Highland Avenue, Madison, WI, 53792, USA
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Heck L, Eggl E, Grandl S, Dierolf M, Jud C, Günther B, Achterhold K, Mayr D, Gleich B, Hellerhoff K, Pfeiffer F, Herzen J. Dose and spatial resolution analysis of grating-based phase-contrast mammography using an inverse Compton x-ray source. J Med Imaging (Bellingham) 2020; 7:023505. [PMID: 32341937 PMCID: PMC7175026 DOI: 10.1117/1.jmi.7.2.023505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 04/06/2020] [Indexed: 11/14/2022] Open
Abstract
Purpose: Although the mortality rate of breast cancer was reduced with the introduction of screening mammography, many women undergo unnecessary subsequent examinations due to inconclusive diagnoses. Superposition of anatomical structures especially within dense breasts in conjunction with the inherently low soft tissue contrast of absorption images compromises image quality. This can be overcome by phase-contrast imaging. Approach: We analyze the spatial resolution of grating-based multimodal mammography using a mammographic phantom and one freshly dissected mastectomy specimen at an inverse Compton x-ray source. Here, the focus was on estimating the spatial resolution with the sample in the beam path and discussing benefits and drawbacks of the method used and the estimation of the mean glandular dose. Finally, the possibility of improving the spatial resolution is investigated by comparing monochromatic grating-based mammography with the standard one. Results: The spatial resolution is constant or also higher for the image acquired with monochromatic radiation and the contrast-to-noise ratio (CNR) is higher in our approach while the dose can be reduced by up to 20%. Conclusions: In summary, phase-contrast imaging helps to improve tumor detection by advanced diagnostic image quality. We demonstrate a higher spatial resolution for one mastectomy specimen and increased CNR at an equal or lower dose for the monochromatic measurements.
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Affiliation(s)
- Lisa Heck
- Technical University of Munich, Chair of Biomedical Physics, Munich School of BioEngineering, Department of Physics, Garching, Germany
| | - Elena Eggl
- Technical University of Munich, Chair of Biomedical Physics, Munich School of BioEngineering, Department of Physics, Garching, Germany
| | - Susanne Grandl
- Ludwig Maximilian University of Munich, Institute for Clinical Radiology, Munich, Germany
| | - Martin Dierolf
- Technical University of Munich, Chair of Biomedical Physics, Munich School of BioEngineering, Department of Physics, Garching, Germany
| | - Christoph Jud
- Technical University of Munich, Chair of Biomedical Physics, Munich School of BioEngineering, Department of Physics, Garching, Germany
| | - Benedikt Günther
- Technical University of Munich, Chair of Biomedical Physics, Munich School of BioEngineering, Department of Physics, Garching, Germany
| | - Klaus Achterhold
- Technical University of Munich, Chair of Biomedical Physics, Munich School of BioEngineering, Department of Physics, Garching, Germany
| | - Doris Mayr
- Ludwig Maximilian University of Munich, Institute of Pathology, Munich, Germany
| | - Bernhard Gleich
- Technical University of Munich, Chair of Biomedical Physics, Munich School of BioEngineering, Department of Physics, Garching, Germany
| | - Karin Hellerhoff
- Ludwig Maximilian University of Munich, Institute for Clinical Radiology, Munich, Germany
| | - Franz Pfeiffer
- Technical University of Munich, Chair of Biomedical Physics, Munich School of BioEngineering, Department of Physics, Garching, Germany.,Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Department of Diagnostic and Interventional Radiology, Munich, Germany
| | - Julia Herzen
- Technical University of Munich, Chair of Biomedical Physics, Munich School of BioEngineering, Department of Physics, Garching, Germany
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5
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Dias CSB, Neto DPA, Baraldi GL, Fonseca MDC. Comparative analysis of sample preparation protocols of soft biological tissues for morphometric studies using synchrotron-based X-ray microtomography. JOURNAL OF SYNCHROTRON RADIATION 2019; 26:2013-2023. [PMID: 31721746 DOI: 10.1107/s1600577519011299] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 08/13/2019] [Indexed: 06/10/2023]
Abstract
The spread of microtomography as a tool for visualization of soft tissues has had a significant impact on a better understanding of complex biological systems. This technique allows a detailed three-dimensional quantitative view of the specimen to be obtained, correlating its morphological organization with its function, providing valuable insights on the functionality of the tissue. Regularly overlooked, but of great importance, proper sample mounting and preparation are fundamental for achieving the highest possible image quality even for the high-resolution imaging systems currently under development. Here, a quantitative analysis compares some of the most common sample-mounting strategies used for synchrotron-based X-ray microtomography of soft tissues: alcoholic-immersion, paraffin-embedding and critical-point drying. These three distinct sample-mounting strategies were performed on the same specimen in order to investigate their impact on sample morphology regardless of individual sample variation. In that sense, the alcoholic-immersion strategy, although causing less shrinkage to the tissue, proved to be the most unsuitable approach for a high-throughput high-resolution imaging experiment due to sample drifting. Also, critical-point drying may present some interesting advantages regarding image quality but is also incompatible with a high-throughput experiment. Lastly, paraffin-embedding is shown to be the most suitable strategy for current soft tissue microtomography experiments. Such detailed analysis of biological sample-mounting strategies for synchrotron-based X-ray microtomography are expected to offer valuable insights on the best approach for using this technique for 3D imaging of soft tissues and following morphometric analysis.
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Affiliation(s)
- Carlos Sato Baraldi Dias
- Brazilian Synchrotron Light National Laboratory, Brazilian Center for Research in Energy and Materials (CNPEM), Giuseppe Maximo Scolfaro 10000, Campinas, São Paulo 13083-970, Brazil
| | - Dionísio Pedro Amorim Neto
- Brazilian Biosciences National Laboratory, Brazilian Center for Research in Energy and Materials (CNPEM), Giuseppe Maximo Scolfaro 10000, Campinas, São Paulo 13083-970, Brazil
| | - Giovanni Lenzi Baraldi
- Brazilian Synchrotron Light National Laboratory, Brazilian Center for Research in Energy and Materials (CNPEM), Giuseppe Maximo Scolfaro 10000, Campinas, São Paulo 13083-970, Brazil
| | - Matheus de Castro Fonseca
- Brazilian Biosciences National Laboratory, Brazilian Center for Research in Energy and Materials (CNPEM), Giuseppe Maximo Scolfaro 10000, Campinas, São Paulo 13083-970, Brazil
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Eggl E, Grandl S, Sztrόkay-Gaul A, Dierolf M, Jud C, Heck L, Burger K, Günther B, Achterhold K, Mayr D, Wilkens JJ, Auweter SD, Gleich B, Hellerhoff K, Reiser MF, Pfeiffer F, Herzen J. Dose-compatible grating-based phase-contrast mammography on mastectomy specimens using a compact synchrotron source. Sci Rep 2018; 8:15700. [PMID: 30356116 PMCID: PMC6200806 DOI: 10.1038/s41598-018-33628-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 08/29/2018] [Indexed: 01/25/2023] Open
Abstract
With the introduction of screening mammography, the mortality rate of breast cancer has been reduced throughout the last decades. However, many women undergo unnecessary subsequent examinations due to inconclusive diagnoses from mammography. Two pathways appear especially promising to reduce the number of false-positive diagnoses. In a clinical study, mammography using synchrotron radiation was able to clarify the diagnosis in the majority of inconclusive cases. The second highly valued approach focuses on the application of phase-sensitive techniques such as grating-based phase-contrast and dark-field imaging. Feasibility studies have demonstrated a promising enhancement of diagnostic content, but suffer from dose concerns. Here we present dose-compatible grating-based phase-contrast and dark-field images as well as conventional absorption images acquired with monochromatic x-rays from a compact synchrotron source based on inverse Compton scattering. Images of freshly dissected mastectomy specimens show improved diagnostic content over ex-vivo clinical mammography images at lower or equal dose. We demonstrate increased contrast-to-noise ratio for monochromatic over clinical images for a well-defined phantom. Compact synchrotron sources could potentially serve as a clinical second level examination.
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Affiliation(s)
- Elena Eggl
- Chair of Biomedical Physics, Department of Physics, Technical University of Munich, James-Franck-Straße 1, 85748, Garching, Germany.
- Munich School of BioEngineering, Technical University of Munich, Boltzmannstraße 11, 85748, Garching, Germany.
| | - Susanne Grandl
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Marchioninistraße 15, 81377, München, Germany
| | - Anikό Sztrόkay-Gaul
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Marchioninistraße 15, 81377, München, Germany
| | - Martin Dierolf
- Chair of Biomedical Physics, Department of Physics, Technical University of Munich, James-Franck-Straße 1, 85748, Garching, Germany
- Munich School of BioEngineering, Technical University of Munich, Boltzmannstraße 11, 85748, Garching, Germany
| | - Christoph Jud
- Chair of Biomedical Physics, Department of Physics, Technical University of Munich, James-Franck-Straße 1, 85748, Garching, Germany
- Munich School of BioEngineering, Technical University of Munich, Boltzmannstraße 11, 85748, Garching, Germany
| | - Lisa Heck
- Chair of Biomedical Physics, Department of Physics, Technical University of Munich, James-Franck-Straße 1, 85748, Garching, Germany
- Munich School of BioEngineering, Technical University of Munich, Boltzmannstraße 11, 85748, Garching, Germany
| | - Karin Burger
- Chair of Biomedical Physics, Department of Physics, Technical University of Munich, James-Franck-Straße 1, 85748, Garching, Germany
- Munich School of BioEngineering, Technical University of Munich, Boltzmannstraße 11, 85748, Garching, Germany
- Department of Radiation Oncology, Klinikum rechts der Isar, Technical University of Munich, Ismaninger Straße 22, 81675, München, Germany
| | - Benedikt Günther
- Chair of Biomedical Physics, Department of Physics, Technical University of Munich, James-Franck-Straße 1, 85748, Garching, Germany
- Munich School of BioEngineering, Technical University of Munich, Boltzmannstraße 11, 85748, Garching, Germany
- Max-Planck-Institute for Quantum Optics, Hans-Kopfermann-Straße 1, 85748, Garching, Germany
| | - Klaus Achterhold
- Chair of Biomedical Physics, Department of Physics, Technical University of Munich, James-Franck-Straße 1, 85748, Garching, Germany
- Munich School of BioEngineering, Technical University of Munich, Boltzmannstraße 11, 85748, Garching, Germany
| | - Doris Mayr
- Institute of Pathology, Ludwig-Maximilians-University München, Thalkirchner Straße 36, 80337, München, Germany
| | - Jan J Wilkens
- Chair of Biomedical Physics, Department of Physics, Technical University of Munich, James-Franck-Straße 1, 85748, Garching, Germany
- Munich School of BioEngineering, Technical University of Munich, Boltzmannstraße 11, 85748, Garching, Germany
- Department of Radiation Oncology, Klinikum rechts der Isar, Technical University of Munich, Ismaninger Straße 22, 81675, München, Germany
| | - Sigrid D Auweter
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Marchioninistraße 15, 81377, München, Germany
| | - Bernhard Gleich
- Munich School of BioEngineering, Technical University of Munich, Boltzmannstraße 11, 85748, Garching, Germany
| | - Karin Hellerhoff
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Marchioninistraße 15, 81377, München, Germany
| | - Maximilian F Reiser
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Marchioninistraße 15, 81377, München, Germany
| | - Franz Pfeiffer
- Chair of Biomedical Physics, Department of Physics, Technical University of Munich, James-Franck-Straße 1, 85748, Garching, Germany
- Munich School of BioEngineering, Technical University of Munich, Boltzmannstraße 11, 85748, Garching, Germany
- Department of Diagnostic and Interventional Radiology, Klinikum rechts der Isar, Technical University of Munich, Ismaninger Straße 22, 81675, München, Germany
| | - Julia Herzen
- Chair of Biomedical Physics, Department of Physics, Technical University of Munich, James-Franck-Straße 1, 85748, Garching, Germany
- Munich School of BioEngineering, Technical University of Munich, Boltzmannstraße 11, 85748, Garching, Germany
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X-Ray Phase-Contrast Technology in Breast Imaging: Principles, Options, and Clinical Application. AJR Am J Roentgenol 2018; 211:133-145. [DOI: 10.2214/ajr.17.19179] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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8
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Tilted grating phase-contrast computed tomography using statistical iterative reconstruction. Sci Rep 2018; 8:6608. [PMID: 29700372 PMCID: PMC5920057 DOI: 10.1038/s41598-018-25075-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 04/13/2018] [Indexed: 11/08/2022] Open
Abstract
Grating-based phase-contrast computed tomography (GBPC-CT) enables increased soft tissue differentiation, but often suffers from streak artifacts when performing high-sensitivity GBPC-CT of biomedical samples. Current GBPC-CT setups consist of one-dimensional gratings and hence allow to measure only the differential phase-contrast (DPC) signal perpendicular to the direction of the grating lines. Having access to the full two-dimensional DPC signal can strongly reduce streak artefacts showing up as characteristic horizontal lines in the reconstructed images. GBPC-CT with gratings tilted by 45° around the optical axis, combining opposed projections, and reconstructing with filtered backprojection is one method to retrieve the full three-dimensional DPC signal. This approach improves the quality of the tomographic data as already demonstrated at a synchrotron facility. However, additional processing and interpolation is necessary, and the approach fails when dealing with cone-beam geometry setups. In this work, we employ the tilted grating configuration with a laboratory GBPC-CT setup with cone-beam geometry and use statistical iterative reconstruction (SIR) with a forward model accounting for diagonal grating alignment. Our results show a strong reduction of streak artefacts and significant increase in image quality. In contrast to the prior approach our proposed method can be used in a laboratory environment due to its cone-beam compatibility.
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9
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Implementation of a Talbot-Lau interferometer in a clinical-like c-arm setup: A feasibility study. Sci Rep 2018; 8:2325. [PMID: 29396417 PMCID: PMC5797080 DOI: 10.1038/s41598-018-19482-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 01/02/2018] [Indexed: 02/07/2023] Open
Abstract
X-ray grating-based phase-contrast imaging has raised interest regarding a variety of potential clinical applications, whereas the method is feasible using a medical x-ray tube. Yet, the transition towards a clinical setup remains challenging due to the requirement of mechanical robustness of the interferometer and high demands applying to medical equipment in clinical use. We demonstrate the successful implementation of a Talbot-Lau interferometer in an interventional c-arm setup. The consequence of vibrations induced by the rotating anode of the tube is discussed and the prototype is shown to provide a visibility of 21.4% at a tube voltage of 60 kV despite the vibrations. Regarding clinical application, the prototype is mainly set back due to the limited size of the field of view covering an area of 17 mm × 46 mm. A c-arm offers the possibility to change the optical axis according to the requirements of the medical examination. We provide a method to correct for artifacts that result from the angulation of the c-arm. Finally, the images of a series of measurements with the c-arm in different angulated positions are shown. Thereby, it is sufficient to perform a single reference measurement in parking position that is valid for the complete series despite angulation.
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10
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Pfeiffer F, Reiser M, Rummeny E. [X‑ray Phase Contrast : Principles, potential and advances in clinical translation]. Radiologe 2018; 58:218-225. [PMID: 29374312 DOI: 10.1007/s00117-018-0357-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
More than 100 years ago Max von Laue in Munich discovered that X‑rays can be interpreted not only as X‑ray quanta in a particle picture, but also show a wave character. This property has been used for a long time in basic research (e.g. in crystallography for determining the structure of proteins), but so far has had no application in medical imaging. In the last 10 years, however, very impressive technological progress could be made in preclinical research, which also makes the utilization of the wave character of X‑ray light possible for medical imaging. These novel radiography procedures, so-called phase-contrast and dark-field imaging, have a great potential for a pronounced improvement in X‑ray imaging and therefore, also the diagnosis of important diseases. This article describes the basic principles of these novel procedures, summarizes the preclinical research results already achieved exemplified by various organs and shows the potential for future clinical utilization in radiography and computed tomography.
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Affiliation(s)
- F Pfeiffer
- Lehrstuhl für Biomedizinische Physik, Department Physik & Munich School of BioEngineering, Technische Universität München, München, Deutschland. .,Institut für diagnostische und interventionelle Radiologie, Klinikum rechts der Isar, Technische Universität München, München, Deutschland.
| | - M Reiser
- Klinik und Poliklinik für Radiologie, Klinikum der Universität, Ludwig-Maximilians-Universität München, München, Deutschland
| | - E Rummeny
- Institut für diagnostische und interventionelle Radiologie, Klinikum rechts der Isar, Technische Universität München, München, Deutschland
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11
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Diagnosis of breast cancer based on microcalcifications using grating-based phase contrast CT. Eur Radiol 2018; 28:3742-3750. [DOI: 10.1007/s00330-017-5158-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 10/19/2017] [Accepted: 10/26/2017] [Indexed: 10/18/2022]
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Ex Vivo Assessment of Coronary Atherosclerotic Plaque by Grating-Based Phase-Contrast Computed Tomography: Correlation With Optical Coherence Tomography. Invest Radiol 2017; 52:223-231. [PMID: 28079701 DOI: 10.1097/rli.0000000000000346] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES The aim of this study was to determine the diagnostic accuracy of grating-based phase-contrast computed tomography (gb-PCCT) to classify and quantify coronary vessel characteristics in comparison with optical coherence tomography (OCT) and histopathology in an ex vivo setting. MATERIALS AND METHODS After excision from 5 heart specimens, 15 human coronary arteries underwent gb-PCCT examination using an experimental imaging setup consisting of a rotating molybdenum anode x-ray tube, a Talbot-Lau grating interferometer, and a single photon counting detector. Subsequently, all vessels were imaged by OCT and histopathologically processed. Optical coherence tomography, gb-PCCT, and histopathology images were manually matched using anatomical landmarks. Optical coherence tomography and gb-PCCT were reviewed by 2 independent observers blinded to histopathology. Vessel, lumen, and plaque area were measured, and plaque characteristics (lipid rich, calcified, and fibrous) were determined for each section. Measures of diagnostic accuracy were derived, applying histopathology as the standard of reference. RESULTS Of a total of 286 assessed cross sections, 241 corresponding sections were included in the statistical analysis. Quantitative measures derived from gb-PCCT were significantly higher than from OCT (P < 0.001) and were strongly correlated with histopathology (Pearson r ≥0.85 for gb-PCCT and ≥0.61 for OCT, respectively). Results of Bland-Altman analysis demonstrated smaller mean differences between OCT and histopathology than for gb-PCCT and histopathology. Limits of agreement were narrower for gb-PCCT with regard to lumen area, for OCT with regard to plaque area, and were comparable with regard to vessel area. Based on histopathology, 228/241 (94.6%) sections were classified as fibrous, calcified, or lipid rich. The diagnostic accuracy of gb-PCCT was excellent for the detection of all plaque components (sensitivity, ≥0.95; specificity, ≥0.94), whereas the results for OCT showed sensitivities of ≥0.73 and specificities of ≥0.66. CONCLUSIONS In this ex vivo setting, gb-PCCT provides excellent results in the assessment of coronary atherosclerotic plaque characteristics and vessel dimensions in comparison to OCT and histopathology. Thus, the technique may serve as adjunct nondestructive modality for advanced plaque characterization in an experimental setting.
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13
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Zeller-Plumhoff B, Roose T, Clough GF, Schneider P. Image-based modelling of skeletal muscle oxygenation. J R Soc Interface 2017; 14:rsif.2016.0992. [PMID: 28202595 DOI: 10.1098/rsif.2016.0992] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Accepted: 01/25/2017] [Indexed: 12/12/2022] Open
Abstract
The supply of oxygen in sufficient quantity is vital for the correct functioning of all organs in the human body, in particular for skeletal muscle during exercise. Disease is often associated with both an inhibition of the microvascular supply capability and is thought to relate to changes in the structure of blood vessel networks. Different methods exist to investigate the influence of the microvascular structure on tissue oxygenation, varying over a range of application areas, i.e. biological in vivo and in vitro experiments, imaging and mathematical modelling. Ideally, all of these methods should be combined within the same framework in order to fully understand the processes involved. This review discusses the mathematical models of skeletal muscle oxygenation currently available that are based upon images taken of the muscle microvasculature in vivo and ex vivo Imaging systems suitable for capturing the blood vessel networks are discussed and respective contrasting methods presented. The review further informs the association between anatomical characteristics in health and disease. With this review we give the reader a tool to understand and establish the workflow of developing an image-based model of skeletal muscle oxygenation. Finally, we give an outlook for improvements needed for measurements and imaging techniques to adequately investigate the microvascular capability for oxygen exchange.
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Affiliation(s)
- B Zeller-Plumhoff
- Helmholtz-Zentrum für Material- und Küstenforschung, Geesthacht, Germany .,Bioengineering Research Group, Faculty of Engineering and the Environment, University of Southampton, Southampton, UK
| | - T Roose
- Bioengineering Research Group, Faculty of Engineering and the Environment, University of Southampton, Southampton, UK
| | - G F Clough
- Faculty of Medicine, University of Southampton, Southampton, UK
| | - P Schneider
- Bioengineering Research Group, Faculty of Engineering and the Environment, University of Southampton, Southampton, UK
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14
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Horn F, Gelse K, Jabari S, Hauke C, Kaeppler S, Ludwig V, Meyer P, Michel T, Mohr J, Pelzer G, Rieger J, Riess C, Seifert M, Anton G. High-energy x-ray Talbot–Lau radiography of a human knee. ACTA ACUST UNITED AC 2017; 62:6729-6745. [DOI: 10.1088/1361-6560/aa7721] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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15
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Coello E, Sperl JI, Bequé D, Benz T, Scherer K, Herzen J, Sztrókay-Gaul A, Hellerhoff K, Pfeiffer F, Cozzini C, Grandl S. Fourier domain image fusion for differential X-ray phase-contrast breast imaging. Eur J Radiol 2017; 89:27-32. [DOI: 10.1016/j.ejrad.2017.01.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 11/25/2016] [Accepted: 01/18/2017] [Indexed: 10/20/2022]
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16
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Arboleda C, Wang Z, Koehler T, Martens G, Van Stevendaal U, Bartels M, Villanueva-Perez P, Roessl E, Stampanoni M. Sensitivity-based optimization for the design of a grating interferometer for clinical X-ray phase contrast mammography. OPTICS EXPRESS 2017; 25:6349-6364. [PMID: 28380987 DOI: 10.1364/oe.25.006349] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
An X-ray grating interferometer (GI) suitable for clinical mammography must comply with quite strict dose, scanning time and geometry limitations, while being able to detect tumors, microcalcifications and other abnormalities. Such a design task is not straightforward, since obtaining optimal phase-contrast and dark-field signals with clinically compatible doses and geometrical constraints is remarkably challenging. In this work, we present a wave propagation based optimization that uses the phase and dark-field sensitivities as figures of merit. This method was used to calculate the optimal interferometer designs for a commercial mammography setup. Its accuracy was validated by measuring the visibility of polycarbonate samples of different thicknesses on a Talbot-Lau interferometer installed on this device and considering some of the most common grating imperfections to be able to reproduce the experimental values. The optimization method outcomes indicate that small grating pitches are required to boost sensitivity in such a constrained setup and that there is a different optimal scenario for each signal type.
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17
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Yin XX, Hadjiloucas S, Chen JH, Zhang Y, Wu JL, Su MY. Tensor based multichannel reconstruction for breast tumours identification from DCE-MRIs. PLoS One 2017; 12:e0172111. [PMID: 28282379 PMCID: PMC5345763 DOI: 10.1371/journal.pone.0172111] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 01/31/2017] [Indexed: 11/18/2022] Open
Abstract
A new methodology based on tensor algebra that uses a higher order singular value decomposition to perform three-dimensional voxel reconstruction from a series of temporal images obtained using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is proposed. Principal component analysis (PCA) is used to robustly extract the spatial and temporal image features and simultaneously de-noise the datasets. Tumour segmentation on enhanced scaled (ES) images performed using a fuzzy C-means (FCM) cluster algorithm is compared with that achieved using the proposed tensorial framework. The proposed algorithm explores the correlations between spatial and temporal features in the tumours. The multi-channel reconstruction enables improved breast tumour identification through enhanced de-noising and improved intensity consistency. The reconstructed tumours have clear and continuous boundaries; furthermore the reconstruction shows better voxel clustering in tumour regions of interest. A more homogenous intensity distribution is also observed, enabling improved image contrast between tumours and background, especially in places where fatty tissue is imaged. The fidelity of reconstruction is further evaluated on the basis of five new qualitative metrics. Results confirm the superiority of the tensorial approach. The proposed reconstruction metrics should also find future applications in the assessment of other reconstruction algorithms.
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Affiliation(s)
- X. -X. Yin
- Centre for Applied Informatics School of Engineering and Science, Victoria University, Melbourne, Australia
- * E-mail: (XXY); (YZ); (JLW)
| | - S. Hadjiloucas
- School of Systems Engineering and Department of Bioengineering, University of Reading, Reading RG6 6AY, United Kingdom
| | - J. -H. Chen
- Tu & Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California, Irvine, CA, United States of America
- Department of Radiology, EDa Hospital and I-Shou University, Kaohsiung, Taiwan
| | - Y. Zhang
- Centre for Applied Informatics School of Engineering and Science, Victoria University, Melbourne, Australia
- School of Computer Science, Fudan University, China
- * E-mail: (XXY); (YZ); (JLW)
| | - J. -L. Wu
- Department of Radiology, Affiliated Zhongshan Hospital of Dalian University, Dalian, Liaoning, China
- * E-mail: (XXY); (YZ); (JLW)
| | - M. -Y. Su
- Tu & Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California, Irvine, CA, United States of America
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18
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Einarsdóttir H, Emerson MJ, Clemmensen LH, Scherer K, Willer K, Bech M, Larsen R, Ersbøll BK, Pfeiffer F. Novelty detection of foreign objects in food using multi-modal X-ray imaging. Food Control 2016. [DOI: 10.1016/j.foodcont.2016.02.023] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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19
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Shearer T, Bradley RS, Hidalgo-Bastida LA, Sherratt MJ, Cartmell SH. Three-dimensional visualisation of soft biological structures by X-ray computed micro-tomography. J Cell Sci 2016; 129:2483-92. [PMID: 27278017 DOI: 10.1242/jcs.179077] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Whereas the two-dimensional (2D) visualisation of biological samples is routine, three-dimensional (3D) imaging remains a time-consuming and relatively specialised pursuit. Current commonly adopted techniques for characterising the 3D structure of non-calcified tissues and biomaterials include optical and electron microscopy of serial sections and sectioned block faces, and the visualisation of intact samples by confocal microscopy or electron tomography. As an alternative to these approaches, X-ray computed micro-tomography (microCT) can both rapidly image the internal 3D structure of macroscopic volumes at sub-micron resolutions and visualise dynamic changes in living tissues at a microsecond scale. In this Commentary, we discuss the history and current capabilities of microCT. To that end, we present four case studies to illustrate the ability of microCT to visualise and quantify: (1) pressure-induced changes in the internal structure of unstained rat arteries, (2) the differential morphology of stained collagen fascicles in tendon and ligament, (3) the development of Vanessa cardui chrysalises, and (4) the distribution of cells within a tissue-engineering construct. Future developments in detector design and the use of synchrotron X-ray sources might enable real-time 3D imaging of dynamically remodelling biological samples.
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Affiliation(s)
- Tom Shearer
- School of Materials, University of Manchester, Manchester M13 9PL, UK School of Mathematics, University of Manchester, Manchester M13 9PL, UK
| | - Robert S Bradley
- Henry Moseley X-ray Imaging Facility, School of Materials, University of Manchester, Manchester M13 9PL, UK
| | | | - Michael J Sherratt
- Institute of Inflammation and Repair, University of Manchester, Manchester M13 9PL, UK
| | - Sarah H Cartmell
- School of Materials, University of Manchester, Manchester M13 9PL, UK
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20
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Meiser J, Willner M, Schröter T, Hofmann A, Rieger J, Koch F, Birnbacher L, Schüttler M, Kunka D, Meyer P, Faisal A, Amberger M, Duttenhofer T, Weber T, Hipp A, Ehn S, Walter M, Herzen J, Schulz J, Pfeiffer F, Mohr J. Increasing the field of view in grating based X-ray phase contrast imaging using stitched gratings. JOURNAL OF X-RAY SCIENCE AND TECHNOLOGY 2016; 24:379-388. [PMID: 27257876 DOI: 10.3233/xst-160552] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Grating based X-ray differential phase contrast imaging (DPCI) allows for high contrast imaging of materials with similar absorption characteristics. In the last years' publications, small animals or parts of the human body like breast, hand, joints or blood vessels have been studied. Larger objects could not be investigated due to the restricted field of view limited by the available grating area. In this paper, we report on a new stitching method to increase the grating area significantly: individual gratings are merged on a carrier substrate. Whereas the grating fabrication process is based on the LIGA technology (X-ray lithography and electroplating) different cutting and joining methods have been evaluated. First imaging results using a 2×2 stitched analyzer grating in a Talbot-Lau interferometer have been generated using a conventional polychromatic X-ray source. The image quality and analysis confirm the high potential of the stitching method to increase the field of view considerably.
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Affiliation(s)
- J Meiser
- Institute of Microstructure Technology, Karlsruhe Institute of Technology Eggenstein-Leopoldshafen, Germany
| | - M Willner
- Department of Physics and Institute of Medical Engineering, Technische Universität München, Garching, Germany
| | - T Schröter
- Institute of Microstructure Technology, Karlsruhe Institute of Technology Eggenstein-Leopoldshafen, Germany
| | - A Hofmann
- Institute for Applied Computer Science, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - J Rieger
- Erlangen Center for Astroparticle Physics, Friedrich - Alexander - Universität Erlangen - Nürnberg, Erlangen, Germany
| | - F Koch
- Institute of Microstructure Technology, Karlsruhe Institute of Technology Eggenstein-Leopoldshafen, Germany
| | - L Birnbacher
- Department of Physics and Institute of Medical Engineering, Technische Universität München, Garching, Germany
| | - M Schüttler
- Institute of Microstructure Technology, Karlsruhe Institute of Technology Eggenstein-Leopoldshafen, Germany
- Department of Physics and Institute of Medical Engineering, Technische Universität München, Garching, Germany
| | - D Kunka
- Institute of Microstructure Technology, Karlsruhe Institute of Technology Eggenstein-Leopoldshafen, Germany
| | - P Meyer
- Institute of Microstructure Technology, Karlsruhe Institute of Technology Eggenstein-Leopoldshafen, Germany
| | - A Faisal
- Institute of Microstructure Technology, Karlsruhe Institute of Technology Eggenstein-Leopoldshafen, Germany
| | - M Amberger
- Institute of Microstructure Technology, Karlsruhe Institute of Technology Eggenstein-Leopoldshafen, Germany
| | | | - T Weber
- Erlangen Center for Astroparticle Physics, Friedrich - Alexander - Universität Erlangen - Nürnberg, Erlangen, Germany
| | - A Hipp
- Department of Physics and Institute of Medical Engineering, Technische Universität München, Garching, Germany
- Institute of Materials Research, Helmholtz-Zentrum Geesthacht, Geesthacht, Germany
| | - S Ehn
- Department of Physics and Institute of Medical Engineering, Technische Universität München, Garching, Germany
| | - M Walter
- Microworks GmbH, Karlsruhe, Germany
| | - J Herzen
- Department of Physics and Institute of Medical Engineering, Technische Universität München, Garching, Germany
| | - J Schulz
- Microworks GmbH, Karlsruhe, Germany
| | - F Pfeiffer
- Department of Physics and Institute of Medical Engineering, Technische Universität München, Garching, Germany
| | - J Mohr
- Institute of Microstructure Technology, Karlsruhe Institute of Technology Eggenstein-Leopoldshafen, Germany
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21
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Gromann LB, Bequé D, Scherer K, Willer K, Birnbacher L, Willner M, Herzen J, Grandl S, Hellerhoff K, Sperl JI, Pfeiffer F, Cozzini C. Low-dose, phase-contrast mammography with high signal-to-noise ratio. BIOMEDICAL OPTICS EXPRESS 2016; 7:381-391. [PMID: 26977347 PMCID: PMC4771456 DOI: 10.1364/boe.7.000381] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Revised: 12/19/2015] [Accepted: 12/20/2015] [Indexed: 06/05/2023]
Abstract
Differential phase-contrast X-ray imaging using a Talbot-Lau interferometer has recently shown promising results for applications in medical imaging. However, reducing the applied radiation dose remains a major challenge. In this study, we consider the realization of a Talbot-Lau interferometer in a high Talbot order to increase the signal-to-noise ratio for low-dose applications. The quantitative performance of π and π/2 systems at high Talbot orders is analyzed through simulations, and the design energy and X-ray spectrum are optimized for mammography. It is found that operation even at very high Talbot orders is feasible and beneficial for image quality. As long as the X-ray spectrum is matched to the visibility spectrum, the SNR continuously increases with the Talbot order for π-systems. We find that the optimal X-ray spectra and design energies are almost independent of the Talbot order and that the overall imaging performance is robust against small variations in these parameters. Discontinuous spectra, such as that from molybdenum, are less robust because the characteristic lines may coincide with minima in the visibility spectra; however, they may offer slightly better performance. We verify this hypothesis by realizing a prototype system with a mean fringe visibility of above 40% at the seventh Talbot order. With this prototype, a proof-of-principle measurement of a freshly dissected breast at reasonable compression to 4 cm is conducted with a mean glandular dose of only 3 mGy but with a high SNR.
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Affiliation(s)
- Lukas B. Gromann
- Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, 85748 Garching,
Germany
- GE Global Research, 85748 Garching,
Germany
| | - Dirk Bequé
- GE Global Research, 85748 Garching,
Germany
| | - Kai Scherer
- Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, 85748 Garching,
Germany
| | - Konstantin Willer
- Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, 85748 Garching,
Germany
| | - Lorenz Birnbacher
- Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, 85748 Garching,
Germany
| | - Marian Willner
- Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, 85748 Garching,
Germany
| | - Julia Herzen
- Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, 85748 Garching,
Germany
| | - Susanne Grandl
- Institute of Clinical Radiology, Ludwig-Maximilians-University Hospital Munich,
Germany
| | - Karin Hellerhoff
- Institute of Clinical Radiology, Ludwig-Maximilians-University Hospital Munich,
Germany
| | | | - Franz Pfeiffer
- Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, 85748 Garching,
Germany
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22
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Scherer K, Willer K, Gromann L, Birnbacher L, Braig E, Grandl S, Sztrókay-Gaul A, Herzen J, Mayr D, Hellerhoff K, Pfeiffer F. Toward Clinically Compatible Phase-Contrast Mammography. PLoS One 2015; 10:e0130776. [PMID: 26110618 PMCID: PMC4481352 DOI: 10.1371/journal.pone.0130776] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 05/22/2015] [Indexed: 11/18/2022] Open
Abstract
Phase-contrast mammography using laboratory X-ray sources is a promising approach to overcome the relatively low sensitivity and specificity of clinical, absorption-based screening. Current research is mostly centered on identifying potential diagnostic benefits arising from phase-contrast and dark-field mammography and benchmarking the latter with conventional state-of-the-art imaging methods. So far, little effort has been made to adjust this novel imaging technique to clinical needs. In this article, we address the key points for a successful implementation to a clinical routine in the near future and present the very first dose-compatible and rapid scan-time phase-contrast mammograms of both a freshly dissected, cancer-bearing mastectomy specimen and a mammographic accreditation phantom.
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Affiliation(s)
- Kai Scherer
- Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, Munich, Germany
- * E-mail:
| | - Konstantin Willer
- Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, Munich, Germany
| | - Lukas Gromann
- Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, Munich, Germany
| | - Lorenz Birnbacher
- Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, Munich, Germany
| | - Eva Braig
- Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, Munich, Germany
| | - Susanne Grandl
- Institute of Clinical Radiology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Anikó Sztrókay-Gaul
- Institute of Clinical Radiology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Julia Herzen
- Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, Munich, Germany
| | - Doris Mayr
- Institute of Pathology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Karin Hellerhoff
- Institute of Clinical Radiology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Franz Pfeiffer
- Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, Munich, Germany
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23
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Improved visualization of breast cancer features in multifocal carcinoma using phase-contrast and dark-field mammography: an ex vivo study. Eur Radiol 2015; 25:3659-68. [PMID: 25956934 PMCID: PMC4636518 DOI: 10.1007/s00330-015-3773-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Revised: 12/19/2014] [Accepted: 04/07/2015] [Indexed: 11/21/2022]
Abstract
Objectives Conventional X-ray attenuation-based contrast is inherently low for the soft-tissue components of the female breast. To overcome this limitation, we investigate the diagnostic merits arising from dark-field mammography by means of certain tumour structures enclosed within freshly dissected mastectomy samples. Methods We performed grating-based absorption, absolute phase and dark-field mammography of three freshly dissected mastectomy samples containing bi- and multifocal carcinoma using a compact, laboratory Talbot-Lau interferometer. Preoperative in vivo imaging (digital mammography, ultrasound, MRI), postoperative histopathological analysis and ex vivo digital mammograms of all samples were acquired for the diagnostic verification of our results. Results In the diagnosis of multifocal tumour growth, dark-field mammography seems superior to standard breast imaging modalities, providing a better resolution of small, calcified tumour nodules, demarcation of tumour boundaries with desmoplastic stromal response and spiculated soft-tissue strands extending from an invasive ductal breast cancer. Conclusions On the basis of selected cases, we demonstrate that dark-field mammography is capable of outperforming conventional mammographic imaging of tumour features in both calcified and non-calcified tumours. Presuming dose optimization, our results encourage further studies on larger patient cohorts to identify those patients that will benefit the most from this promising additional imaging modality. Key Points • X-ray dark-field mammography provides significantly improved visualization of tumour features • X-ray dark-field mammography is capable of outperforming conventional mammographic imaging • X-ray dark-field mammography provides imaging sensitivity towards highly dispersed calcium grains
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24
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Non-invasive differentiation of kidney stone types using X-ray dark-field radiography. Sci Rep 2015; 5:9527. [PMID: 25873414 PMCID: PMC4397641 DOI: 10.1038/srep09527] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2014] [Accepted: 03/11/2015] [Indexed: 02/01/2023] Open
Abstract
Treatment of renal calculi is highly dependent on the chemical composition of the stone in question, which is difficult to determine using standard imaging techniques. The objective of this study is to evaluate the potential of scatter-sensitive X-ray dark-field radiography to differentiate between the most common types of kidney stones in clinical practice. Here, we examine the absorption-to-scattering ratio of 118 extracted kidney stones with a laboratory Talbot-Lau Interferometer. Depending on their chemical composition, microscopic growth structure and morphology the various types of kidney stones show strongly varying, partially opposite contrasts in absorption and dark-field imaging. By assessing the microscopic calculi morphology with high resolution micro-computed tomography measurements, we illustrate the dependence of dark-field signal strength on the respective stone type. Finally, we utilize X-ray dark-field radiography as a non-invasive, highly sensitive (100%) and specific (97%) tool for the differentiation of calcium oxalate, uric acid and mixed types of stones, while additionally improving the detectability of radio-lucent calculi. We prove clinical feasibility of the here proposed method by accurately classifying renal stones, embedded within a fresh pig kidney, using dose-compatible measurements and a quick and simple visual inspection.
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25
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Koehler T, Daerr H, Martens G, Kuhn N, Löscher S, van Stevendaal U, Roessl E. Slit-scanning differential x-ray phase-contrast mammography: Proof-of-concept experimental studies. Med Phys 2015; 42:1959-65. [DOI: 10.1118/1.4914420] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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26
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Wang H, Kashyap Y, Sawhney K. Hard-X-ray directional dark-field imaging using the speckle scanning technique. PHYSICAL REVIEW LETTERS 2015; 114:103901. [PMID: 25815933 DOI: 10.1103/physrevlett.114.103901] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Indexed: 06/04/2023]
Abstract
X-ray dark-field imaging can provide inaccessible and complementary information compared to conventional absorption contrast imaging. However, extraction of the dark-field signal is difficult, and sophisticated optics are often required. In this Letter, we report a novel approach to generate high-quality dark-field images using a simple membrane. The dark-field image is extracted from the maximum correlation coefficient by applying a cross-correlation algorithm to a stack of speckle images collected by scanning a membrane in a transverse direction to the incident x-ray beam. The new method can also provide directional dark-field information, which is extremely useful for the study of strongly ordered systems. The potential of the proposed technique for nondestructive x-ray imaging is demonstrated by imaging representative samples.
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Affiliation(s)
- Hongchang Wang
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, United Kingdom
| | - Yogesh Kashyap
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, United Kingdom
| | - Kawal Sawhney
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, United Kingdom
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