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Title: Edge illumination X-ray phase tomography of multi-material samples using a single-image phase retrieval algorithm

Authors:
; ; ; ; ;
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1356747
Grant/Contract Number:
AC02-06CH11357
Resource Type:
Journal Article: Published Article
Journal Name:
Optics Express
Additional Journal Information:
Journal Volume: 25; Journal Issue: 10; Related Information: CHORUS Timestamp: 2017-05-12 14:38:26; Journal ID: ISSN 1094-4087
Publisher:
Optical Society of America (OSA)
Country of Publication:
United States
Language:
English

Citation Formats

Zamir, Anna, Diemoz, Paul C., Vittoria, Fabio A., Hagen, Charlotte K., Endrizzi, Marco, and Olivo, Alessandro. Edge illumination X-ray phase tomography of multi-material samples using a single-image phase retrieval algorithm. United States: N. p., 2017. Web. doi:10.1364/OE.25.011984.
Zamir, Anna, Diemoz, Paul C., Vittoria, Fabio A., Hagen, Charlotte K., Endrizzi, Marco, & Olivo, Alessandro. Edge illumination X-ray phase tomography of multi-material samples using a single-image phase retrieval algorithm. United States. doi:10.1364/OE.25.011984.
Zamir, Anna, Diemoz, Paul C., Vittoria, Fabio A., Hagen, Charlotte K., Endrizzi, Marco, and Olivo, Alessandro. Fri . "Edge illumination X-ray phase tomography of multi-material samples using a single-image phase retrieval algorithm". United States. doi:10.1364/OE.25.011984.
@article{osti_1356747,
title = {Edge illumination X-ray phase tomography of multi-material samples using a single-image phase retrieval algorithm},
author = {Zamir, Anna and Diemoz, Paul C. and Vittoria, Fabio A. and Hagen, Charlotte K. and Endrizzi, Marco and Olivo, Alessandro},
abstractNote = {},
doi = {10.1364/OE.25.011984},
journal = {Optics Express},
number = 10,
volume = 25,
place = {United States},
year = {Fri May 12 00:00:00 EDT 2017},
month = {Fri May 12 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1364/OE.25.011984

Citation Metrics:
Cited by: 2works
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  • Purpose: A number of different techniques have been developed to reduce radiation dose in x-ray computed tomography (CT) imaging. In this paper, the authors will compare task-based measures of image quality of CT images reconstructed by two algorithms: conventional filtered back projection (FBP), and a new iterative reconstruction algorithm (IR). Methods: To assess image quality, the authors used the performance of a channelized Hotelling observer acting on reconstructed image slices. The selected channels are dense difference Gaussian channels (DDOG).A body phantom and a head phantom were imaged 50 times at different dose levels to obtain the data needed to assessmore » image quality. The phantoms consisted of uniform backgrounds with low contrast signals embedded at various locations. The tasks the observer model performed included (1) detection of a signal of known location and shape, and (2) detection and localization of a signal of known shape. The employed DDOG channels are based on the response of the human visual system. Performance was assessed using the areas under ROC curves and areas under localization ROC curves. Results: For signal known exactly (SKE) and location unknown/signal shape known tasks with circular signals of different sizes and contrasts, the authors’ task-based measures showed that a FBP equivalent image quality can be achieved at lower dose levels using the IR algorithm. For the SKE case, the range of dose reduction is 50%–67% (head phantom) and 68%–82% (body phantom). For the study of location unknown/signal shape known, the dose reduction range can be reached at 67%–75% for head phantom and 67%–77% for body phantom case. These results suggest that the IR images at lower dose settings can reach the same image quality when compared to full dose conventional FBP images. Conclusions: The work presented provides an objective way to quantitatively assess the image quality of a newly introduced CT IR algorithm. The performance of the model observers using the IR images was always higher than that seen using the FBP images in the authors’ SKE and SKE location unknown detection tasks. To achieve a FBP-equivalent image quality in CT systems, the authors can lower the radiation dose by using this IR image reconstruction algorithm. Further studies are warranted using clinical data and human observer to validate these results for more complicated and realistic tasks.« less
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  • Quantitative phase tomography was evaluated by using a differential phase microscope with a Foucault knife-edge scanning filter. A 3D x-ray phase image of polystyrene beads was obtained at 5.4 keV. The reconstructed refractive index was fairly good agreement with the Henke’s tabulated data.
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