Boosting phase contrast with two-arm interferometers using sub-micron period gratings
Dr Han Wen, National Institute of Health, USA
Abstract
Grating interferometers of very high line density operate in the far field regime, where the incident beam is split into widely separated beams, which are then redirected to coherently interfere with each other. Because of the wide separation of the interfering beams, far field interferometers can provide high levels of phase contrast. They also provide absolute phase images in some cases. We report on imaging experiments using a symmetric three-grating interferometer of 200 nm period, operating at 22.5 keV and 1.5% spectral bandwidth on the 2-BM beamline of APS. The gratings consist of arrays of multi-layer stacks on a staircase substrate, which are fabricated in a thin-film deposition process. Using a slitted incident beam we acquired absolute phase images of lightly absorbing samples. Visible light versions of the interferometer have been shown to work with polychromatic sources. Our future aim is to adapt the method to compact x-ray sources.
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Dr Han Wen, National Institute of Health, USA
Dr Han Wen, National Institute of Health, USA
"Dr Wen obtained a B.S. in Physics from Peking University in Beijing, China, and graduated with a Ph.D. in Physics from the University of Maryland, College Park, Maryland, USA, through the CUSPEA Scholarship. He has been a Principle Investigator at the National Heart, Lung and Blood Institute of the National Institutes of Health since 1997. His research has been focused on imaging technologies for medical applications, including x-ray imaging and cardio-vascular MRI technologies."
Clinical XPCi-based mammography with synchrotron radiation
Dr Maura Tonutti, Cattinara Hospital, Italy
Abstract
The first clinical study in phase contrast mammography has been completed in Trieste (Italy): the study has involved 71 patients with questionable or suspicious breast abnormalities identified at the hospital by means of standard digital mammography together with ultrasonography. The final results of this study are now available and can be regarded as the starting point of further investigations. Moreover, this first clinical experience was characterized by the use of a screen-film system. As digital detectors with high spatial resolution (pixel size of ∼50μm) have recently become commercially available, they have been considered for future clinical experiments: a second clinical study, which utilizes a computed radiology system on a limited number of patients, has already been undertaken.
Both qualitative and quantitative (diagnostic) analysis of the results will be presented and the possible role of the XPCi-based mammography will be discussed considering all the new imaging techniques available for breast imaging.
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Dr Maura Tonutti, Cattinara Hospital, Italy
Dr Maura Tonutti, Cattinara Hospital, Italy
"Dr Maura Tonutti-
• Graduated Medical School at the University of Trieste on 31st October 1990 with the following grade : 110/110 cum laude.
• Completed Diagnostic Radiology residency programme in Trieste on 15 th December 1990 with the following grade : 70/70 cum laude.
• Senology School certificate in 1993
• Working as Radiologist for the Radiology Department at the University of Trieste since 1st of July 1993
• Dealing with Senology and Ultrasound Imaging since 1991; and with Magnetic Resonance Imaging applied to breast since 2000.
• Cooperating with SYRMEP (Synchrotron Radiation for medical Physics) project since 1991 focusing on Synchrotron Ray Mammography.
• Actively working with multidisciplinary senology work group officially recognized by University Hospital since 2001.
• Registered SIRM sections of Senology and Ultrasound Imaging
Registered Italian School of Senology.
• Head of Senology section at the Radiology Department of the University of Trieste since January 2006.
• License for reading Breast Screening x-rays in 2006 after passing all the tests of the regional education programme at CSPO in Florence"
Medicine, material science and security: the versatility of the coded-aperture approach
Dr Peter Munro, The University of Western Australia
Abstract
The principal limitation to the widespread deployment of X-ray phase imaging in a variety of applications is probably versatility. A versatile X-ray phase imaging system must be able to work with polychromatic and non-microfocus sources such as those currently used in medical and industrial applications, have physical dimensions sufficiently large to accommodate samples of interest, be insensitive to environmental disturbances such as vibrations and temperature variations, require only simple system setup and maintenance and be able to perform quantitative imaging. The coded aperture technique, based upon the edge illumination principle, satisfies each of these criteria. To date we have applied the technique to mammography, materials science, small animal imaging, non-destructive testing and security. In this talk we will outline the theory of coded aperture phase imaging and show several examples of where the technique has been applied to practical problems.
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Dr Peter Munro, The University of Western Australia
Dr Peter Munro, The University of Western Australia
"Peter Munro currently works in the Optical + Biomedical Engineering Laboratory and Centre for Microscopy, Characterisation and Analysis at the University of Western Australia where he is supported by an Australian Research Council discovery early career research award. He works on the development of models of light interaction with biological tissue with the objective of bringing innovation to biomedical imaging techniques. Prior to this, he worked in the Radiation Physics group at University College London where he developed a quantitative method for performing X-ray phase contrast imaging using incoherent sources. Dr Munro received a Commonwealth scholarship in 2002 and subsequently completed his PhD in the physics department at Imperial College London in 2006 on the use of numerical methods in the modelling of high numerical aperture optical imaging systems. He received a BSc and a BEng with honours, both from the University of Western Australia, in 1998 and 2000 respectively."
Phase contrast X-ray imaging in the clinic: a first mammography study
Professor Marco Stampanoni, ETH Zurich, and Paul Scherrer Institut, Switzerland
Abstract
Phase-contrast and scattering-based x-ray imaging are known to provide additional and complementary information to conventional, absorption-based methods. We present the results of a multicenter, international reader study aiming at the evaluation of the clinical relevance of phase contrast mammography. Freshly dissected whole breast specimens of 33 patients with histo-pathologically proven breast cancer were imaged using a Talbot-Lau interferometer equipped with a conventional x- ray tube (40 kVp, 28 keV, 25 mA). Absorption, differential phase and small-angle scattering signals were combined into novel, high-frequency-enhanced radiographic images and compared to digital mammography images. Six expert breast radiologists evaluated clinically relevant parameters such as general image quality, presence of artifacts, and visibility of diagnostic features (i.e. lesion conspicuity and skin infiltration) on a 5-point-scale. The study indicates that phase contrast enhanced mammograms show a better image quality concerning sharpness, lesions delineation, and visibility of microcalcifications, resulting in a general improvement of their clinical relevance.
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Professor Marco Stampanoni, ETH Zurich, and Paul Scherrer Institut, Switzerland
Professor Marco Stampanoni, ETH Zurich, and Paul Scherrer Institut, Switzerland
"Professor Dr Marco Stampanoni studied physics at the Swiss Federal Institute of Technology Zürich (ETHZ) and obtained his MSc in November 998. He enrolled in a PhD program at the Institute for Biomedical Engineering (IBT) at the ETHZ and at the same time, he started a Master of Advanced Studies in Medical Physics, successfully concluded in October 2000. The subject of his physics PhD, defended in 2002, was the development of a novel approach towards X-ray computed tomography at the micron scale. In 2004 he was appointed beamline scientist and initiated the TOMCAT project, a beamline for Tomographic Microscopy and Coherent Radiology experiments at the Swiss Light Source. Stampanoni was appointed Head of the X-ray Tomographic Microscopy Group in 2005 and Assistant Professor (Tenure Track) for X-ray Microscopy at the Department for Information Technology and Electrical Engineering (D-ITET) of ETH Zürich in 2008. He is affiliated with the Institute for Biomedical Engineering (IBT) of the University and ETH Zürich and still heads his team at PSI."
Clinical XPCi-based mammography with synchrotron radiation
Professor Renata Longo, University of Trieste
Abstract
The first clinical study in phase contrast mammography has been completed in Trieste (Italy): the study has involved 71 patients with questionable or suspicious breast abnormalities identified at the hospital by means of standard digital mammography together with ultrasonography. The final results of this study are now available and can be regarded as the starting point of further investigations. Moreover, this first clinical experience was characterized by the use of a screen-film system. As digital detectors with high spatial resolution (pixel size of ∼50μm) have recently become commercially available, they have been considered for future clinical experiments: a second clinical study, which utilizes a computed radiology system on a limited number of patients, has already been undertaken.
Both qualitative and quantitative (diagnostic) analysis of the results will be presented and the possible role of the XPCi-based mammography will be discussed considering all the new imaging techniques available for breast imaging.
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Professor Renata Longo, University of Trieste
Professor Renata Longo, University of Trieste
"Renata Longo is Associate Professor of Medical Physics at the University of Trieste, Italy and associate researcher of the Italian National Institute of Nuclear Physics (INFN). Responsible of the University of Trieste for the program of mammography with synchotron radiation in cooperation with the synchrotron radiation laboratory Elettra and the Trieste university hospital. In this framework the first clinical study in free space propagarion phase contrast mammography is completed and new programs are going on. Present researchs: (a) Phase sensitive techniques for breast imaging and tomography with synchrotron radiation, including development of dedicated imaging detectors, (b) NMR medical imaging for human brain mapping.
Reviewer for international journals of physics and radiology and for scientific institutions and laboratories. Author of more than 100 papers in international scientific journals. "