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Zhou, T., Zanette, I., Zdora, M.-C., Lundström, U., Larsson, D. H., Hertz, H. M., . . . Burvall, A. (2015). Speckle-based x-ray phase-contrast imaging with a laboratory source and the scanning technique. Optics Letters, 40(12), 2822-2825
Öppna denna publikation i ny flik eller fönster >>Speckle-based x-ray phase-contrast imaging with a laboratory source and the scanning technique
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2015 (Engelska)Ingår i: Optics Letters, ISSN 0146-9592, E-ISSN 1539-4794, Vol. 40, nr 12, s. 2822-2825Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

The speckle-based scanning method for x-ray phase-contrast imaging is implemented with a liquid-metal-jet source. Using the two-dimensional scanning technique, the phase shift introduced by the object is retrieved in both transverse orientations, and the limitations on spatial resolution inherent to the speckle-tracking technique are avoided. This method opens up possibilities of new high-resolution multimodal applications for lab-based phasecontrast x-ray imaging.

Ort, förlag, år, upplaga, sidor
Optics Info Base, Optical Society of America, 2015
Nationell ämneskategori
Annan fysik
Identifikatorer
urn:nbn:se:kth:diva-170677 (URN)10.1364/OL.40.002822 (DOI)000356234300038 ()26076271 (PubMedID)
Forskningsfinansiär
Knut och Alice Wallenbergs StiftelseVetenskapsrådet
Anmärkning

QC 20150707

Tillgänglig från: 2015-07-07 Skapad: 2015-07-03 Senast uppdaterad: 2017-12-04Bibliografiskt granskad
Zanette, I., Zdora, M.-C. -., Zhou, T., Burvall, A., Larsson, D. H., Thibault, P., . . . Pfeiffer, F. (2015). X-ray microtomography using correlation of near-field speckles for material characterization. Proceedings of the National Academy of Sciences of the United States of America, 112(41), 12569-12573
Öppna denna publikation i ny flik eller fönster >>X-ray microtomography using correlation of near-field speckles for material characterization
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2015 (Engelska)Ingår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 112, nr 41, s. 12569-12573Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Nondestructive microscale investigation of objects is an invaluable tool in life and materials sciences. Currently, such investigation is mainly performed with X-ray laboratory systems, which are based on absorption-contrast imaging and cannot access the information carried by the phase of the X-ray waves. The phase signal is, nevertheless, of great value in X-ray imaging as it is complementary to the absorption information and in general more sensitive to visualize features with small density differences. Synchrotron facilities, which deliver a beam of high brilliance and high coherence, provide the ideal condition to develop such advanced phase-sensitive methods, but their access is limited. Here we show how a small modification of a laboratory setup yields simultaneously quantitative and 3D absorption and phase images of the object. This single-shot method is based on correlation of X-ray near-field speckles and represents a significant broadening of the capabilities of laboratory- based X-ray tomography.

Ort, förlag, år, upplaga, sidor
National Academy of Sciences, 2015
Nyckelord
Microtomography, Near-field speckles, Phase-contrast imaging, Refractive index measurement, X-ray imaging, chemical analysis, Conference Paper, correlation analysis, image analysis, micro-computed tomography, priority journal, refraction index
Nationell ämneskategori
Fysik
Identifikatorer
urn:nbn:se:kth:diva-181135 (URN)10.1073/pnas.1502828112 (DOI)2-s2.0-84944200781 (Scopus ID)
Anmärkning

QC 20160216

Tillgänglig från: 2016-02-16 Skapad: 2016-01-29 Senast uppdaterad: 2017-11-30Bibliografiskt granskad
Zhou, T., Lundström, U., Thüring, T., Rutishauser, S., Larsson, D. H., Stampanoni, M., . . . Burvall, A. (2014). Comparison of propagation-and grating-based x-ray phase-contrast imaging techniques with a liquid-metal-jet source. In: Medical Imaging 2014: Physics of Medical Imaging. Paper presented at Medical Imaging 2014: Physics of Medical Imaging; San Diego, CA; United States; 17 February 2014 through 20 February 2014 (pp. 903353). SPIE - International Society for Optical Engineering
Öppna denna publikation i ny flik eller fönster >>Comparison of propagation-and grating-based x-ray phase-contrast imaging techniques with a liquid-metal-jet source
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2014 (Engelska)Ingår i: Medical Imaging 2014: Physics of Medical Imaging, SPIE - International Society for Optical Engineering, 2014, s. 903353-Konferensbidrag, Publicerat paper (Refereegranskat)
Abstract [en]

X-ray phase-contrast imaging has been developed as an alternative to conventional absorption imaging, partly for its dose advantage over absorption imaging at high resolution. Grating-based imaging (GBI) and propagation-based imaging (PBI) are two phase-contrast techniques used with polychromatic laboratory sources. We compare the two methods by experiments and simulations with respect to required dose. A simulation method based on the projection approximation is designed and verified with experiments. A comparison based on simulations of the doses required for detection of an object with respect to its diameter is presented, showing that for monochromatic radiation, there is a dose advantage for PBI for small features but an advantage for GBI at larger features. However, GBI suffers more from the introduction of polychromatic radiation, in this case so much that PBI gives lower dose for all investigated feature sizes. Furthermore, we present and compare experimental images of biomedical samples. While those support the dose advantage of PBI, they also highlight the GBI advantage of quantitative reconstruction of multimaterial samples. For all experiments a liquid-metal-jet source was used. Liquid-metal-jet sources are a promising option for laboratory-based phase-contrast imaging due to the relatively high brightness and small spot size.

Ort, förlag, år, upplaga, sidor
SPIE - International Society for Optical Engineering, 2014
Serie
Progress in Biomedical Optics and Imaging, ISSN 1605-7422 ; 9033
Nyckelord
grating-based, phase-contrast, propagation-based, X-ray imaging
Nationell ämneskategori
Medicinsk bildbehandling
Identifikatorer
urn:nbn:se:kth:diva-146812 (URN)10.1117/12.2043417 (DOI)000338775800173 ()2-s2.0-84901626184 (Scopus ID)978-081949826-7 (ISBN)
Konferens
Medical Imaging 2014: Physics of Medical Imaging; San Diego, CA; United States; 17 February 2014 through 20 February 2014
Anmärkning

QC 20140616

Tillgänglig från: 2014-06-16 Skapad: 2014-06-16 Senast uppdaterad: 2014-09-08Bibliografiskt granskad
Lundström, U., Larsson, D. H., Westermark, U. K., Burvall, A. & Hertz, H. M. (2014). Small-Animal microangiography using phase-contrast X-ray imaging and gas as contrast agent. In: Medical Imaging 2014: Physics of Medical Imaging. Paper presented at Medical Imaging 2014: Physics of Medical Imaging; San Diego, CA; United States; 17 February 2014 through 20 February 2014 (pp. 90331L). SPIE - International Society for Optical Engineering
Öppna denna publikation i ny flik eller fönster >>Small-Animal microangiography using phase-contrast X-ray imaging and gas as contrast agent
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2014 (Engelska)Ingår i: Medical Imaging 2014: Physics of Medical Imaging, SPIE - International Society for Optical Engineering, 2014, s. 90331L-Konferensbidrag, Publicerat paper (Refereegranskat)
Abstract [en]

We use propagation-based phase-contrast X-ray imaging with gas as contrast agent To visualize The microvasculature in small animals like mice and rats. The radiation dose required for absorption X-ray imaging is proportional To The minus fourth power of The structure size To be detected. This makes small vessels impossible To image at reasonable radiation doses using The absorption of conventional iodinated contrast agents. Propagation-based phase contrast gives enhanced contrast for high spatial frequencies by moving The detector away from The sample To let phase variations in The Transmitted X-rays develop into intensity variations at The detector. Blood vessels are normally difficult To observe in phase contrast even with iodinated contrast agents as The density difference between blood and most Tissues is relatively small. By injecting gas into The blood stream This density difference can be greatly enhanced giving strong phase contrast. One possible gas To use is carbon dioxide, which is a clinically accepted X-ray contrast agent. The gas is injected into The blood stream of patients To Temporarily displace The blood in a region and Thereby reduce The X-ray absorption in The blood vessels. We have shown That This method can be used To image blood vessels down To 8 μm in diameter in mouse ears. The low dose requirements of This method indicate a potential for live small-Animal imaging and longitudinal studies of angiogenesis.

Ort, förlag, år, upplaga, sidor
SPIE - International Society for Optical Engineering, 2014
Serie
Progress in Biomedical Optics and Imaging, ISSN 1605-7422 ; 9033
Nyckelord
X-ray, phase contrast, propagation-based phase contrast, angiography, contrast agent
Nationell ämneskategori
Medicinsk bildbehandling
Identifikatorer
urn:nbn:se:kth:diva-146783 (URN)10.1117/12.2043705 (DOI)000338775800054 ()2-s2.0-84901594060 (Scopus ID)978-081949826-7 (ISBN)
Konferens
Medical Imaging 2014: Physics of Medical Imaging; San Diego, CA; United States; 17 February 2014 through 20 February 2014
Anmärkning

QC 20140617

Tillgänglig från: 2014-06-17 Skapad: 2014-06-16 Senast uppdaterad: 2014-08-19Bibliografiskt granskad
Zanette, I., Zhou, T., Burvall, A., Lundström, U., Larsson, D. H., Zdora, M., . . . Hertz, H. M. (2014). Speckle-Based X-Ray Phase-Contrast and Dark-Field Imaging with a Laboratory Source. Physical Review Letters, 112(25), 253903
Öppna denna publikation i ny flik eller fönster >>Speckle-Based X-Ray Phase-Contrast and Dark-Field Imaging with a Laboratory Source
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2014 (Engelska)Ingår i: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 112, nr 25, s. 253903-Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

We report on the observation and application of near-field speckles with a laboratory x-ray source. The detection of speckles is possible thanks to the enhanced brilliance properties of the used liquid-metal-jet source, and opens the way to a range of new applications in laboratory-based coherent x-ray imaging. Here, we use the speckle pattern for multimodal imaging of demonstrator objects. Moreover, we introduce algorithms for phase and dark-field imaging using speckle tracking, and we show that they yield superior results with respect to existing methods.

Ort, förlag, år, upplaga, sidor
American Physical Society, 2014
Nyckelord
Scattering, Information, Tomography, Retrieval
Nationell ämneskategori
Annan fysik
Identifikatorer
urn:nbn:se:kth:diva-148281 (URN)10.1103/PhysRevLett.112.253903 (DOI)000338284900009 ()2-s2.0-84903522889 (Scopus ID)
Forskningsfinansiär
EU, FP7, Sjunde ramprogrammet, StG 240142 279753
Anmärkning

QC 20140807

Tillgänglig från: 2014-08-07 Skapad: 2014-08-05 Senast uppdaterad: 2017-12-05Bibliografiskt granskad
Lundström, U., Westermark, U. K., Larsson, D. H., Burvall, A., Arsenian Henriksson, M. & Hertz, H. M. (2014). X-ray phase contrast with injected gas for tumor microangiography. Physics in Medicine and Biology, 59(11), 2801-2811
Öppna denna publikation i ny flik eller fönster >>X-ray phase contrast with injected gas for tumor microangiography
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2014 (Engelska)Ingår i: Physics in Medicine and Biology, ISSN 0031-9155, E-ISSN 1361-6560, Vol. 59, nr 11, s. 2801-2811Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

We show that the microvasculature of mouse tumors can be visualized using propagation-based phase-contrast x-ray imaging with gas as the contrast agent. The large density difference over the gas-tissue interface provides high contrast, allowing the imaging of small-diameter blood vessels with relatively short exposure times and low dose using a compact liquid-metal-jet x-ray source. The method investigated is applied to tumors (E1A/Ras-transformed mouse embryonic fibroblasts) grown in mouse ears, demonstrating sub-15-mu m-diameter imaging of their blood vessels. The exposure time for a 2D projection image is a few seconds and a full tomographic 3D map takes some minutes. The method relies on the strength of the vasculature to withstand the gas pressure. Given that tumor vessels are known to be more fragile than normal vessels, we investigate the tolerance of the vasculature of 12 tumors to gas injection and find that a majority withstand 200 mbar pressures, enough to fill 12-mu m-diameter vessels with gas. A comparison of the elasticity of tumorous and non-tumorous vessels supports the assumption of tumor vessels being more fragile. Finally, we conclude that the method has the potential to be extended to the imaging of 15 mu m vessels in thick tissue, including mouse imaging, making it of interest for, e.g., angiogenesis research.

Nyckelord
x-ray, phase-contrast, angiography, tumor, propagation-based, microangiography, gas
Nationell ämneskategori
Radiologi och bildbehandling
Identifikatorer
urn:nbn:se:kth:diva-139504 (URN)10.1088/0031-9155/59/11/2801 (DOI)000336459000016 ()2-s2.0-84900469948 (Scopus ID)
Forskningsfinansiär
VetenskapsrådetCancerfonden
Anmärkning

QC 20140624. Updated from manuscript to article in journal.

Tillgänglig från: 2014-01-14 Skapad: 2014-01-14 Senast uppdaterad: 2017-12-06Bibliografiskt granskad
Zhou, T., Lundström, U., Thüring, T., Rutishauser, S., Larsson, D. H., Stampanoni, M., . . . Burvall, A. (2013). Comparison of two x-ray phase-contrast imaging methods with a microfocus source. Optics Express, 21(25), 30183-30195
Öppna denna publikation i ny flik eller fönster >>Comparison of two x-ray phase-contrast imaging methods with a microfocus source
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2013 (Engelska)Ingår i: Optics Express, ISSN 1094-4087, E-ISSN 1094-4087, Vol. 21, nr 25, s. 30183-30195Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

We present a comparison for high-resolution imaging with a laboratory source between grating-based (GBI) and propagation-based (PBI) x-ray phase-contrast imaging. The comparison is done through simulations and experiments using a liquid-metal-jet x-ray microfocus source. Radiation doses required for detection in projection images are simulated as a function of the diameter of a cylindrical sample. Using monochromatic radiation, simulations show a lower dose requirement for PBI for small object features and a lower dose for GBI for larger object features. Using polychromatic radiation, such as that from a laboratory microfocus source, experiments and simulations show a lower dose requirement for PBI for a large range of feature sizes. Tested on a biological sample, GBI shows higher noise levels than PBI, but its advantage of quantitative refractive index reconstruction for multi-material samples becomes apparent.

Nyckelord
Computed-Tomography, Grating Interferometer, Noise, Propagation, Performance, Retrieval, Signal, Jet, CT
Nationell ämneskategori
Annan fysik
Identifikatorer
urn:nbn:se:kth:diva-139423 (URN)10.1364/OE.21.030183 (DOI)000328575700007 ()2-s2.0-84890505484 (Scopus ID)
Forskningsfinansiär
Vetenskapsrådet
Anmärkning

QC 20140113

Tillgänglig från: 2014-01-13 Skapad: 2014-01-13 Senast uppdaterad: 2017-12-06Bibliografiskt granskad
Larsson, D. H., Lundström, U., Westermark, U. K., Arsenian Henriksson, M., Burvall, A. & Hertz, H. M. (2013). First application of liquid-metal-jet sources for small-animal imaging: High-resolution CT and phase-contrast tumor demarcation. Medical physics (Lancaster), 40(2), 021909
Öppna denna publikation i ny flik eller fönster >>First application of liquid-metal-jet sources for small-animal imaging: High-resolution CT and phase-contrast tumor demarcation
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2013 (Engelska)Ingår i: Medical physics (Lancaster), ISSN 0094-2405, Vol. 40, nr 2, s. 021909-Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Purpose: Small-animal studies require images with high spatial resolution and high contrast due to the small scale of the structures. X-ray imaging systems for small animals are often limited by the microfocus source. Here, the authors investigate the applicability of liquid-metal-jet x-ray sources for such high-resolution small-animal imaging, both in tomography based on absorption and in soft-tissue tumor imaging based on in-line phase contrast. Methods: The experimental arrangement consists of a liquid-metal-jet x-ray source, the small-animal object on a rotating stage, and an imaging detector. The source-to-object and object-to-detector distances are adjusted for the preferred contrast mechanism. Two different liquid-metal-jet sources are used, one circulating a Ga/In/Sn alloy and the other an In/Ga alloy for higher penetration through thick tissue. Both sources are operated at 40-50 W electron-beam power with similar to 7 mu m x-ray spots, providing high spatial resolution in absorption imaging and high spatial coherence for the phase-contrast imaging. Results: High-resolution absorption imaging is demonstrated on mice with CT, showing 50 mu m bone details in the reconstructed slices. High-resolution phase-contrast soft-tissue imaging shows clear demarcation of mm-sized tumors at much lower dose than is required in absorption. Conclusions: This is the first application of liquid-metal-jet x-ray sources for whole-body small-animal x-ray imaging. In absorption, the method allows high-resolution tomographic skeletal imaging with potential for significantly shorter exposure times due to the power scalability of liquid-metal-jet sources. In phase contrast, the authors use a simple in-line arrangement to show distinct tumor demarcation of few-mm-sized tumors. This is, to their knowledge, the first small-animal tumor visualization with a laboratory phase-contrast system.

Nyckelord
small-animal imaging, liquid-metal-jet, x-ray, CT, tumor demarcation, mouse
Nationell ämneskategori
Annan fysik
Identifikatorer
urn:nbn:se:kth:diva-119468 (URN)10.1118/1.4788661 (DOI)000314727700038 ()23387757 (PubMedID)2-s2.0-84873576570 (Scopus ID)
Forskningsfinansiär
VetenskapsrådetVinnova
Anmärkning

QC 20130319

Tillgänglig från: 2013-03-19 Skapad: 2013-03-14 Senast uppdaterad: 2017-12-06Bibliografiskt granskad
Zhou, T., Lundström, U., Larsson, D. H., Hertz, H. M. & Burvall, A. (2013). Low-dose phase-contrast X-ray imaging: a comparison of two methods. In: 11th International Conference On X-Ray Microscopy (XRM2012): . Paper presented at 11th International Conference on X-ray Microscopy (XRM), AUG 05-10, 2012, Shanghai, China (pp. 012041). Institute of Physics (IOP)
Öppna denna publikation i ny flik eller fönster >>Low-dose phase-contrast X-ray imaging: a comparison of two methods
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2013 (Engelska)Ingår i: 11th International Conference On X-Ray Microscopy (XRM2012), Institute of Physics (IOP), 2013, s. 012041-Konferensbidrag, Publicerat paper (Refereegranskat)
Abstract [en]

Propagation- and grating-based X-ray phase-contrast imaging methods are compared theoretically. As a prospective application of phase-contrast methods in medical or small animal imaging, carbon dioxide (CO2) angiography is the simulated task. The required dose for the observable blood vessel is compared through simulation. The result indicates that the propagation-based method requires lower dose in this application.

Ort, förlag, år, upplaga, sidor
Institute of Physics (IOP), 2013
Serie
Journal of Physics Conference Series, ISSN 1742-6588 ; 463
Nyckelord
Interferometer
Nationell ämneskategori
Annan fysik
Identifikatorer
urn:nbn:se:kth:diva-139245 (URN)10.1088/1742-6596/463/1/012041 (DOI)000327949000041 ()2-s2.0-84890533898 (Scopus ID)
Konferens
11th International Conference on X-ray Microscopy (XRM), AUG 05-10, 2012, Shanghai, China
Anmärkning

QC 20140110

Tillgänglig från: 2014-01-10 Skapad: 2014-01-08 Senast uppdaterad: 2014-01-14Bibliografiskt granskad
Burvall, A., Larsson, D. H., Lundström, U., Stig, F., Hallström, S. & Hertz, H. M. (2013). Phase-retrieval methods with applications in composite-material tomography. In: 11th International Conference On X-Ray Microscopy (XRM2012): . Paper presented at 11th International Conference on X-ray Microscopy (XRM), AUG 05-10, 2012, Shanghai, China (pp. 012015). Institute of Physics Publishing (IOPP)
Öppna denna publikation i ny flik eller fönster >>Phase-retrieval methods with applications in composite-material tomography
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2013 (Engelska)Ingår i: 11th International Conference On X-Ray Microscopy (XRM2012), Institute of Physics Publishing (IOPP), 2013, s. 012015-Konferensbidrag, Publicerat paper (Refereegranskat)
Abstract [en]

In-line phase-contrast x-ray imaging is emerging as a method for observing small details when the contrast in absorption x-ray imaging is low. It gives images with strong edge enhancement, and phase retrieval is necessary to obtain quantitative thickness information. In particular for tomography, clarity can be enhanced by phase retrieval, as here demonstrated on a 3D-weave reinforced composite material. Seven suitable phase-retrieval methods are identified and integrated into a single method, where each version is marked by variations in particular steps. The general method and its variations are outlined and a comparison shows which methods are most suitable in different situations.

Ort, förlag, år, upplaga, sidor
Institute of Physics Publishing (IOPP), 2013
Serie
Journal of Physics Conference Series, ISSN 1742-6588 ; 463
Nyckelord
Contrast Tomography, Formulas, Distance, Objects
Nationell ämneskategori
Annan fysik
Identifikatorer
urn:nbn:se:kth:diva-139242 (URN)10.1088/1742-6596/463/1/012015 (DOI)000327949000015 ()2-s2.0-84891284501 (Scopus ID)
Konferens
11th International Conference on X-ray Microscopy (XRM), AUG 05-10, 2012, Shanghai, China
Anmärkning

QC 20140113

Tillgänglig från: 2014-01-13 Skapad: 2014-01-08 Senast uppdaterad: 2015-03-31Bibliografiskt granskad
Organisationer
Identifikatorer
ORCID-id: ORCID iD iconorcid.org/0000-0003-3804-0561

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