Standard xray imaging techniques like radiography or computed tomography ct rely on a decrease of the xray beams intensity attenuation when. The experimental results have demonstrated that the structures, such as the corpus callosum, the optic chiasma, and the caudate nucleus, could be clearly depicted. Phase retrieval in xray imaging based on using structured. Computational techniques in propagationbased xray phase imaging. Computational techniques in propagationbased xray phase. New xray computed tomography methods for research and industry. Propagationbased phasecontrast xray imaging newsmedical. Coan, theoretical comparison of three xray phasecontrast imaging techniques. Pdf propagationbased phasecontrast xray imaging at a. Phasecontrast xray imaging pci or phasesensitive xray imaging is a general term for. Advanced 3d imaging of uterine leiomyomas morphology by.
Propagation based phase contrast uses freespace propagation to get edge enhancement, talbot and polychromatic farfield interferometry uses a set of diffraction gratings to measure the derivative of the phase, refractionenhanced imaging uses an analyzer crystal also for differential measurement, and x ray interferometry uses a crystal. The x ray phase contrast imaging has been applied to visualize overall rootsoil interactions. Recently, certain plant specimens have been observed using the laboratory based x ray phase contrast ct 26, 27. Phase contrast imaging is an advanced x ray imaging technology that can capture the refraction and phase shift of x ray waves when they pass through objects 10, 11, 12. Xray propagationbased equally sloped tomography for mouse. Propagationbased phasecontrast xray imaging at a compact light source article pdf available in scientific reports 71. However, the method adapted herein, known as propagation based phase contrast imaging but also as refraction enhanced imaging, is a. Absorption and phase contrast xray imaging in paleontology. Biofilm imaging in porous media by laboratory xray. Phasesensitive detection shows promise for improved contrast where absorption is insuf.
Two of the commonly used phase contrast imaging techniques are analyser based ab imaging, which is sensitive to phase variations lying in the diffraction plane of the analyser crystal, and propagation based pb imaging, which uses freespace propagation to convert phase shifts. Optimization of propagationbased phasecontrast imaging at a. Visualization of internal 3d structure of small live seed. Forward model for propagationbased xray phase contrast imaging. The latter denomination derives from the fact that the experimental setup of this method is basically the same as in conventional radiography. Contrast enhancement of propagation based xray phase. Imaging tests are among the many diagnostic tools used by physicians to diagnose and even treat disease. Phase retrieval in xray phasecontrast imaging suitable. Comparison of propagationbased ct using synchrotron. Various x ray phase contrast imaging techniques have been developed and applied over the last twenty years in different domains, such as material sciences, biology and medicine.
Phasecontrast imaging with a compact xray light source. Theoretical comparison of three xray phasecontrast imaging. Highresolution and quantitative xray phasecontrast. X ray tomography is a powerful tool giving access to the morphology of biofilms, in 3d porous media, at the mesoscale. Radiation imaging in propagationbased phase contrast modality at different. Jan 23, 2020 to evaluate and compare the image quality of propagation based phase contrast computed tomography pbct using synchrotron radiation and conventional conebeam breast computed tomography cbbct based on various radiological image quality criteria. The italian phase contrast imaging flagship node is based on the syrmep. Propagation based xray phasecontrast imaging technique. Introduction classical medical threedimensional xray imaging systems computed tomography, ct rely on absorption for contrast 1. However, wet seeds during the germination have never been observed due to their low absorption contrast. Review of x ray phase contrast imaging techniques and propagation based imaging using a benchtop microfocal source bradley, david and gondogdu, ozcan and jenneson, paul and nirgianaki, eleftheria and elna herawati che ismail, 2007. With x ray attenuation techniques, the softtissue contrast is not substantial because the differences in densities of different components of breast soft tissue are small. Phasecontrast xray imaging pci or phasesensitive xray imaging is a general term for different technical methods that use information concerning changes in the phase of an xray beam that passes through an object in order to create its images. This interference is fundamental because it encodes precious information on the phase of the x ray waves, zanette explained.
Basics of the propagation based xray phasecontrast imaging. Whereas conventional x ray imaging is based on x rays attenuation, xpc exploits the phase shift induced by the object on the x rays. Optimization of propagationbased phasecontrast imaging. The comparison is done through simulations and experiments using a liquidmetaljet xray microfocus source. Propagationbased xray phase contrast for biomedical imaging, author gureyev, t e and mayo, s c and nesterets, ya and pogany, a and stevenson, a w and wilkins, s w and myers, d e and department of medicine and paganin, d m and school of physics, monash university, victoria 3800, abstractnote absorptioncontrast xray imaging. Noise texture and signal detectability in propagation. The comparison is done through simulations and experiments using a liquidmetaljet x ray microfocus source. Several applications have confirmed the higher sensitivity of xpc compared with conventional radiology, sometimes opening new applications that were previously impossible using conventional x ray imaging. Until now, the use of contrast agents such as barium sulfate, silvercoated. Radiation doses required for detection in projection images are simulated as a function of the diameter of a cylindrical sample.
Mareike topperwien, regine gradl, daniel keppeler, malte vassholz, alexander meyer, roland hessler, klaus achterhold, bernhard gleich, martin dierolf, franz pfeiffer, tobias moser and tim salditt, propagationbased phasecontrast xray tomography of cochlea using a compact synchrotron source, scientific reports, 10. Development of hard xray phasecontrast imaging csiropedia. Propagationbased phasecontrast xray tomography of cochlea using a compact synchrotron source. Ct device, two synchrotronbased imaging setups using conventional absorption and propagationbased phase contrast, and a commercial xray microscope with a lenscoupled detector system, dedicated for radiography and. Sep 05, 2014 we demonstrate a quantitative x ray phase contrast imaging xpci technique derived from propagation dependent phase change. Xray phase tomography enhanced with synchrotron radiation. Results of the cochlea obtained with a more optimized setup for propagationbased imaging with a. X ray phase contrast imaging has attracted interest in recent years. Phase contrast imaging flagship node trieste euro bioimaging. Experimental comparison of grating and propagationbased. Stateofthearttechniques for phase retrieval in propagation based xray phasecontrast imaging are aiming to solve an underdetermined linear system of equations. Article is made available in accordance with the publishers policy and may be subject to us law.
Image quality and radiation dose in propagation based. Optimisation of a propagationbased xray phasecontrast microct. Forward model for propagationbased xray phase contrast imaging in parallel and conebeam geometry. Propagationbased phasecontrast xray imaging at a compact. The image contrast in conventional absorption radiography is obtained from variations in the xray absorption imaginary term of the object. Comparison of two xray phasecontrast imaging methods. Eight excised breast tissue samples of various sizes and containing different lesion types were scanned using pbct at a synchrotron facility and. Propagation based phase contrast x ray imaging is the simplest of the existing phase contrast methods as it does not require any additional optics. Mar 14, 2016 visualizing this phase shift can increase the overall image contrast and permit detection of details that are classically considered x ray transparent, such as the interfaces between soft tissues. Some time later, a related letter to nature was submitted with the title phasecontrast imaging with polychromatic xrays and appeared in a november 1996 issue.
Phase contrast x ray imaging is an emerging modality that has shown promise to image and characterize weakly absorbing objects, such as threedimensional printed plastics and imaging breast tissue. Exploring xray phase tomography with synchrotron radiation. We demonstrate the applicability of propagation based x ray phase contrast imaging at a laserassisted compact light source with known phantoms and the lungs and airways of a mouse. Seventh framework program under grant agreement no 291763 and. Results are presented of the experiment at the syrmep beamline of elettra synchrotron using the propagation based phase contrast mammographic tomography method, which incorporates not only absorption, but also x ray phase information. X ray beam for planar and computed microtomography microct imaging. Demonstration of synchrotron xray phase contrast imaging. Whole heart detailed and quantitative anatomy, myofibre. Propagationbased phasecontrast xray imaging is a term used to describe various. Propagationbased phasecontrast xray imaging at a compact light source.
Phase retrieval methods for polychromatic propagation. Pdf absorptioncontrast xray imaging serves to visualize the variation in xray attenuation within the volume of a given. Phase retrieval in inline xray phase contrast imaging. Unification of analyserbased and propagationbased xray. This paper presents a study on the optimization of synchrotron xray propagationbased phasecontrast imaging computed tomography pcict for threedimensional 3d visualization and assessment of the hydrogel cardiac patches. Phase retrieval in xray phasecontrast imaging suitable for.
Oct 23, 2014 the research team used the phase contrast x ray imaging technique, which works by making the x ray beam interfere while it propagates from sample to detector. Single distance x ray propagation based phase contrast imaging is considered as a simple method compared to those requiring additional precise instruments and sophisticated algorithms to retrieve phase images. New xray computed tomography methods for research and. Propagation based phase contrast x ray computed tomography is a valuable tool for highresolution visualization of biological samples, giving distinct improvements in terms of contrast and dose. Due to the high water content of biofilms, the attenuation coefficient of biofilms and water are very close, hindering the distinction between biofilms and water without the use of contrast agents. Xray propagationbased equally sloped tomography for. Some of the x ray phase contrast imaging methods require highly monochromatic plane wave radiation and sophisticated x ray optics wilkins et al. A subset of these techniques use free space propagation to generate phase contrast and phase can be recovered by inverting differential equations. Optimization of propagationbased xray phasecontrast. We demonstrate the applicability of propagationbased xray phasecontrast imaging at a laserassisted compact light source with known phantoms and the lungs and airways of a mouse.
Sep 17, 2014 xray phase imaging utilizes a variety of techniques to render phase information as intensity contrast and these intensity images can in some cases be processed to retrieve quantitative phase. Review of xray phase contrast imaging techniques and. Comparison of two xray phasecontrast imaging methods with a. Theoretical comparison of three xray phasecontrast imaging techniques. Visualization of internal 3d structure of small live seed on. However, no comprehensive intercomparison exists in the literature. Oct 21, 2014 this image shows a noninvasive slice of a rats heart tissue made with x ray phase tomography by propagation based imaging, which provides sharper data with higher resolution than phase. Absorptioncontrast xray imaging serves to visualize the variation in xray.
First, alginate hydrogel was 3dprinted into cardiac patches, with the pores filled by fibrin. Propagationbased xray phasecontrast tomography of mastectomy. X ray propagation based phase contrast imaging combined with equally sloped tomography ppciest has been used for the nondestructive 3d imaging of the mouse brain. Jul 22, 2019 cartilage and soft tissue imaging using x rays. Phase retrieval methods for polychromatic propagationbased. The aim of this study was to optimise the experimental protocol and data analysis for invivo breast cancer x ray imaging. Propagation based imaging pbi is the most common name for this technique but it is also called inline holography, refractionenhanced imaging or phase contrast radiography. Unlike xray absorptionbased imaging methods, phasecontrast imaging pci. Indeed, differently from the xray absorptionbased imaging, where the contrast originates from attenuation mismatches between different tissues inside a sample, in the xrpci the contrast is due to the phaseshift. Baran p et al 2017 optimization of propagationbased xray phasecontrast tomography for breast cancer imaging phys. Contrast enhancement of propagation based xray phase contrast imaging.
We present here a theoretical study that compares three among the most used techniques. The refractive index of the materials in the xray region can be expressed as, where is the xray wavelength. Ct technique expands possibilities of imaging ancient remains. Osa theoretical comparison of three xray phasecontrast. Potential of propagationbased synchrotron xray phasecontrast. Different tomographic setups were tested to visualize the fossilized inner structures. We assume that the absorption and phase components are correlated and solve the transport of intensity equation tie. Propagationbased phasecontrast computed tomography pbct is a method for threedimensional xray imaging that utilizes refraction, as well as absorption, of xrays in the tissues to. Fast threedimensional phase retrieval in propagationbased xray.