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Yang JS, Jeon SY, Choi JH. Acquisition of a single grid-based phase-contrast X-ray image using instantaneous frequency and noise filtering. Biomed Eng Online 2022; 21:92. [PMID: 36575491 PMCID: PMC9793636 DOI: 10.1186/s12938-022-01061-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 12/20/2022] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND To obtain phase-contrast X-ray images, single-grid imaging systems are effective, but Moire artifacts remain a significant issue. The solution for removing Moire artifacts from an image is grid rotation, which can distinguish between these artifacts and sample information within the Fourier space. However, the mechanical movement of grid rotation is slower than the real-time change in Moire artifacts. Thus, Moire artifacts generated during real-time imaging cannot be removed using grid rotation. To overcome this problem, we propose an effective method to obtain phase-contrast X-ray images using instantaneous frequency and noise filtering. RESULT The proposed phase-contrast X-ray image using instantaneous frequency and noise filtering effectively suppressed noise with Moire patterns. The proposed method also preserved the clear edge of the inner and outer boundaries and internal anatomical information from the biological sample, outperforming conventional Fourier analysis-based methods, including absorption, scattering, and phase-contrast X-ray images. In particular, when comparing the phase information for the proposed method with the x-axis gradient image from the absorption image, the proposed method correctly distinguished two different types of soft tissue and the detailed information, while the latter method did not. CONCLUSION This study successfully achieved a significant improvement in image quality for phase-contrast X-ray images using instantaneous frequency and noise filtering. This study can provide a foundation for real-time bio-imaging research using three-dimensional computed tomography.
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Affiliation(s)
- Jae-Suk Yang
- grid.255649.90000 0001 2171 7754Division of Mechanical and Biomedical Engineering, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul, 03760 Republic of Korea
| | - Sun-Young Jeon
- grid.255649.90000 0001 2171 7754Division of Mechanical and Biomedical Engineering, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul, 03760 Republic of Korea
| | - Jang-Hwan Choi
- grid.255649.90000 0001 2171 7754Division of Mechanical and Biomedical Engineering, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul, 03760 Republic of Korea
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Guo P, Wang Z, Wu C, Zhu X, Zhang L. Iterative signal retrieval for X-ray grating interferometry with dual-shot. J Xray Sci Technol 2022; 30:891-901. [PMID: 35694949 DOI: 10.3233/xst-221162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
BACKGROUND X-ray grating interferometry normally requires multiple steps and exposures, causing a prolonged imaging time. There is motivation to use fewer steps to reduce scanning time and complexity, while keeping fidelity of the retrieved signals. OBJECTIVE We propose an iterative signal retrieval method, extracting attenuation, dark field contrast (DFC), and differential phase contrast (DPC) signals from two X-ray exposures. METHODS Two shots were captured at G2 grating positions with difference of 1/4 grating period. The algorithm consists of two stages. At the first stage, amplitude of sample phase stepping curve retrieved by virtual phase stepping (VPS) method, visibility and local phase of background phase stepping curve are used to limit the results to the proximity of the ground truth. After the second stage, three high-quality parameters, amplitude, visibility, and local phase, are retrieved through finetuning, and three signals are calculated. Simulated and real-sample experiments were conducted to validate this method. RESULTS We used standard phase stepping result as benchmark and calculated structural similarity (SSIM) and peak signal-to-noise ratio (PSNR) between benchmark and parameters retrieved by our dual-shot method and virtual phase stepping (VPS) method. For both simulated and real-sample experiments, the SSIM and PSNR value of dual-shot method are higher than those of VPS method. For real-sample method, we also conducted a three-step PS, and the SSIM and PSNR value of dual-shot method are slightly lower than those of three-step PS. CONCLUSION Using our dual-shot method demonstrates higher performance than other single-shot method in retrieving high-quality signals, and it also reduces radiation dose and time.
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Affiliation(s)
- Peiyuan Guo
- Department of Engineering Physics, Tsinghua University, Beijing, China
- Key Laboratory of Particle & Radiation Imaging (Tsinghua University) of Ministry of Education, Beijing, China
| | - Zhentian Wang
- Department of Engineering Physics, Tsinghua University, Beijing, China
- Key Laboratory of Particle & Radiation Imaging (Tsinghua University) of Ministry of Education, Beijing, China
| | - Chengpeng Wu
- Department of Engineering Physics, Tsinghua University, Beijing, China
- Key Laboratory of Particle & Radiation Imaging (Tsinghua University) of Ministry of Education, Beijing, China
| | - Xiaohua Zhu
- Department of Engineering Physics, Tsinghua University, Beijing, China
- Key Laboratory of Particle & Radiation Imaging (Tsinghua University) of Ministry of Education, Beijing, China
| | - Li Zhang
- Department of Engineering Physics, Tsinghua University, Beijing, China
- Key Laboratory of Particle & Radiation Imaging (Tsinghua University) of Ministry of Education, Beijing, China
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Zhang X, Su T, Yang J, Zhu J, Xia D, Zheng H, Liang D, Ge Y. Performance evaluation of dual-energy CT and differential phase contrast CT in quantitative imaging applications. Med Phys 2021; 49:1123-1138. [PMID: 34951037 DOI: 10.1002/mp.15417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 11/29/2021] [Accepted: 11/29/2021] [Indexed: 11/05/2022] Open
Abstract
PURPOSE The purpose of this study is to evaluate and compare the quantitative material decomposition performance of the dual-energy CT (DECT) and differential phase contrast CT (DPCT) via numerical observer studies. METHODS The electron density (ρe ) and the effective atomic number (Zeff ) are selected as the decomposition bases. The image domain based decomposition algorithms with certain noise suppression are used to extract the ρe and Zeff information under three different spatial resolutions (0.3 mm, 0.1 mm, and 0.03 mm). The contrast-to-noise-ratio (CNR) and the numerical human observer model which is sensitive to the noise textures are investigated to compare the quantitative imaging performance of DECT and DPCT under varied radiation dose levels. RESULTS The model observer results show that the DECT is superior to DPCT at 0.3 mm spatial resolution (300 mm object size); the DECT and DPCT show similar quantitative imaging performance at 0.1 mm spatial resolution (100 mm object size); and the DPCT outperforms the DECT by approximately 1.5 times for the 0.3 mm sized imaging target at 0.03 mm spatial resolution (30 mm object size). CONCLUSIONS In conclusion, the DECT would be recommended to obtain ρe and Zeff for the low spatial resolution quantitative imaging applications such as the diagnostic CT imaging. Whereas, the DPCT would be recommended for ultra high spatial resolution imaging tasks of small objects such as the micro-CT imaging. This study provides a reference to determine the most appropriate quantitative X-ray CT imaging method for a certain radiation dose level. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Xin Zhang
- Key Laboratory of Low-grade Energy Utilization Technologies and Systems of Ministry of Education of China, College of Power Engineering, Chongqing University, Chongqing, 400044, China.,Research Center for Medical Artificial Intelligence, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Ting Su
- Research Center for Medical Artificial Intelligence, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Jiecheng Yang
- Research Center for Medical Artificial Intelligence, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Jiongtao Zhu
- Research Center for Medical Artificial Intelligence, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Dongmei Xia
- Key Laboratory of Low-grade Energy Utilization Technologies and Systems of Ministry of Education of China, College of Power Engineering, Chongqing University, Chongqing, 400044, China
| | - Hairong Zheng
- Paul C Lauterbur Research Center for Biomedical Imaging, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Dong Liang
- Research Center for Medical Artificial Intelligence, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China.,Paul C Lauterbur Research Center for Biomedical Imaging, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Yongshuai Ge
- Research Center for Medical Artificial Intelligence, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China.,Paul C Lauterbur Research Center for Biomedical Imaging, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
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He Q, Wang Y, Li P, Yao C, Zhang J, Fu T, Zhang K, Yuan Q, Huang W, Wang S, Zhu P, Liu P. Accurate reconstruction algorithm for bilateral differential phase signals. Radiat Detect Technol Methods 2021. [DOI: 10.1007/s41605-021-00273-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Wu Z, Gao K, Wang Z, Wang S, Zhu P, Ren Y, Tian Y. Generalized reverse projection method for grating-based phase tomography. J Synchrotron Radiat 2021; 28:854-863. [PMID: 33949993 DOI: 10.1107/s1600577521001806] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Accepted: 02/14/2021] [Indexed: 06/12/2023]
Abstract
The reverse projection protocol results in fast phase-contrast imaging thanks to its compatibility with conventional computed-tomography scanning. Many researchers have proposed variants. However, all these reverse projection methods in grating-based phase-contrast imaging are built on the hypothesis of the synchronous phase of reference shifting curves in the whole field of view. The hypothesis imposes uniformity and alignment requirements on the gratings, thus the field of view is generally limited. In this paper, a generalized reverse projection method is presented analytically for the case of non-uniform reference in grating-based phase tomography. The method is demonstrated by theoretical derivation, numerical simulations and synchrotron radiation experiments. The influence of imaging position to sensitivity, and the phase-wrapping phenomenon are also discussed. The proposed method combines the advantages of the high efficiency of the reverse projection method and the universal applicability of the phase-stepping method. The authors believe that the method would be used widely in fast and dose-constrained imaging.
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Affiliation(s)
- Zhao Wu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029, People's Republic of China
| | - Kun Gao
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029, People's Republic of China
| | - Zhili Wang
- School of Electronic Science and Applied Physics, Hefei University of Technology, Hefei, Anhui 230009, People's Republic of China
| | - Shengxiang Wang
- Institute of High-Energy Physics, Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Peiping Zhu
- Institute of High-Energy Physics, Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Yuqi Ren
- Shanghai Synchrotron Radiation Facility, Chinese Academy of Sciences, Shanghai 201204, People's Republic of China
| | - Yangchao Tian
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029, People's Republic of China
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Abstract
Numerous advances have been made in X-ray technology in recent years. X-ray imaging plays an important role in the nondestructive exploration of the internal structures of objects. However, the contrast of X-ray absorption images remains low, especially for materials with low atomic numbers, such as biological samples. X-ray phase-contrast images have an intrinsically higher contrast than absorption images. In this review, the principles, milestones, and recent progress of X-ray phase-contrast imaging methods are demonstrated. In addition, prospective applications are presented.
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Liu P, Yang J, Chen J, Su T, Guo J, Zheng H, Liang D, Ge Y. Model-driven phase retrieval network for single-shot x-ray Talbot-Lau interferometer imaging. Opt Lett 2020; 45:6314-6317. [PMID: 33186978 DOI: 10.1364/ol.402917] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 10/08/2020] [Indexed: 06/11/2023]
Abstract
The single-shot x-ray Talbot-Lau interferometer-based differential phase contrast (DPC) imaging is able to accelerate time-consuming data acquisition; however, the extracted phase image suffers from severe image artifacts. Here, we propose to estimate the DPC image via a deep convolutional neural network (CNN) incorporated with the physical imaging model. Instead of training the CNN with thousands of labeled data beforehand, both phantom and biological specimen validation experiments show that high-quality DPC images can be automatically generated from only one single-shot projection image with a certain periodic moiré pattern. This work provides a new, to the best of our knowledge, paradigm for single-shot x-ray DPC imaging.
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Ge Y, Liu P, Ni Y, Chen J, Yang J, Su T, Zhang H, Guo J, Zheng H, Li Z, Liang D. Enhancing the X-Ray Differential Phase Contrast Image Quality With Deep Learning Technique. IEEE Trans Biomed Eng 2020; 68:1751-1758. [PMID: 32746069 DOI: 10.1109/tbme.2020.3011119] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE The purpose of this work is to investigate the feasibility of using deep convolutional neural network (CNN) to improve the image quality of a grating-based X-ray differential phase contrast imaging (XPCI) system. METHODS In this work, a novel deep CNN based phase signal extraction and image noise suppression algorithm (named as XP-NET) is developed. The numerical phase phantom, the ex vivo biological specimen and the ACR breast phantom are evaluated via the numerical simulations and experimental studies, separately. Moreover, images are also evaluated under different low radiation levels to verify its dose reduction capability. RESULTS Compared with the conventional analytical method, the novel XP-NET algorithm is able to reduce the bias of large DPC signals and hence increasing the DPC signal accuracy by more than 15%. Additionally, the XP-NET is able to reduce DPC image noise by about 50% for low dose DPC imaging tasks. CONCLUSION This proposed novel end-to-end supervised XP-NET has a great potential to improve the DPC signal accuracy, reduce image noise, and preserve object details. SIGNIFICANCE We demonstrate that the deep CNN technique provides a promising approach to improve the grating-based XPCI performance and its dose efficiency in future biomedical applications.
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Ge Y, Chen J, Zhu P, Yang J, Deng S, Shi W, Zhang K, Guo J, Zhang H, Zheng H, Liang D. Dual phase grating based X-ray differential phase contrast imaging with source grating: theory and validation. Opt Express 2020; 28:9786-9801. [PMID: 32225579 DOI: 10.1364/oe.381759] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 01/12/2020] [Indexed: 06/10/2023]
Abstract
In this work, we developed a new theoretical framework using wave optics to explain the working mechanism of the grating based X-ray differential phase contrast imaging (XPCI) interferometer systems consist of more than one phase grating. Under the optical reversibility principle, the wave optics interpretation was simplified into the geometrical optics interpretation, in which the phase grating was treated as a thin lens. Moreover, it was derived that the period of an arrayed source, e.g., the period of a source grating, is always equal to the period of the diffraction fringe formed on the source plane. When a source grating is utilized, the theory indicated that it is better to keep the periods of the two phase gratings different to generate large period diffraction fringes. Experiments were performed to validate these theoretical findings.
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Wang Z, Shi X, Ren K, Chen H, Ren Y, Gao K, Wu Z. Transmission, refraction and dark-field retrieval in hard X-ray grating interferometry. J Synchrotron Radiat 2020; 27:494-502. [PMID: 32153290 DOI: 10.1107/s1600577519017223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2019] [Accepted: 12/25/2019] [Indexed: 06/10/2023]
Abstract
A three-image algorithm is proposed to retrieve the sample's transmission, refraction and dark-field information in hard X-ray grating interferometry. Analytical formulae of the three-image algorithm are theoretically derived and presented, and evaluated by proof-of-principle synchrotron radiation experiments. The results confirm the feasibility of the proposed algorithm. The novelty of the proposed algorithm is that it allows versatile and tunable multimodal X-ray imaging by substantially relaxing the existing limitations on the lateral grating position. Furthermore, this algorithm can also be adapted for samples with negligible refraction, reducing the number of required sample measurements to two. Furthermore, the noise properties of the retrieved images are investigated in terms of the standard deviations. Theoretical models are presented and verified by synchrotron radiation measurements. It is shown that the noise standard deviations exhibit strong dependence on the lateral grating position, especially in the case of refraction and dark-field images. Further noise reduction and dose reduction can thus be possible by optimizing the lateral grating position for a selected region of interest. Those results can serve as general guidelines to optimize the data acquisition scheme for specific applications and problems.
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Affiliation(s)
- Zhili Wang
- School of Electronic Science and Applied Physics, Hefei University of Technology, Anhui 230009, People's Republic of China
| | - Xiaomin Shi
- School of Electronic Science and Applied Physics, Hefei University of Technology, Anhui 230009, People's Republic of China
| | - Kun Ren
- School of Electronic Science and Applied Physics, Hefei University of Technology, Anhui 230009, People's Republic of China
| | - Heng Chen
- School of Electronic Science and Applied Physics, Hefei University of Technology, Anhui 230009, People's Republic of China
| | - Yuqi Ren
- Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204, People's Republic of China
| | - Kun Gao
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Anhui 230026, People's Republic of China
| | - Zhao Wu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Anhui 230026, People's Republic of China
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Ji X, Zhang R, Li K, Chen GH. Is high sensitivity always desirable for a grating-based differential phase contrast imaging system? Med Phys 2019; 47:1215-1228. [PMID: 31872886 DOI: 10.1002/mp.13984] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 12/10/2019] [Accepted: 12/10/2019] [Indexed: 11/08/2022] Open
Abstract
PURPOSE In grating-based x-ray differential phase contrast (DPC) imaging, the measured signal amplitude of the phase shift induced by an image object is proportional to the so-called system sensitivity. Therefore, to achieve a better signal-to-noise (SNR) for improved imaging performance, it is generally believed that one should increase the system sensitivity by reducing the period of the analyzer grating or increasing the distance between the phase grating and analyzer grating. The purpose of this work is to theoretically and experimentally demonstrate that there is an optimal system sensitivity to attain the highest SNR for a given task provided that the standard phase-stepping acquisition and phase retrieval methods are used. When system sensitivity goes beyond this optimal value, SNR decreases and the imaging performance deteriorates. METHODS Due to the fundamental fact that the measured phase signal is a cyclic variable, the phase wrapping effect is inevitable in DPC imaging when the system sensitivity increases. The phase wrapping effect appears in both signal and noise measurements. The effect in the signal measurement is manifested in the so-called signal statistical bias and such effect often impacts the accuracy of the measurement. The phase wrapping effect also appears in the noise variance measurement and impacts the precision of the measurement. A thorough theoretical analysis was performed in this work to demonstrate the quantitative impacts of phase wrapping on both signal bias and noise variance and thus on the actual system SNR. The joint effect of phase wrapping in both the signal bias and noise variance yields an optimal system sensitivity to achieve the highest SNR. Both extensive numerical simulation studies and experimental studies were performed to validate the theoretical analysis. RESULTS Both theoretical analysis and experimental studies show that the SNR of the DPC signal is not always proportional to the sensitivity due to the cyclic nature of the signal and the phase wrapping effect. For a given refraction angle and exposure level, there exists an optimal sensitivity factor that maximizes the SNR, beyond which, increasing the sensitivity will decrease the SNR. CONCLUSIONS Increase of system sensitivity does not always improve x-ray DPC imaging performance provided that the standard phase-stepping acquisition and phase retrieval methods are used.
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Affiliation(s)
- Xu Ji
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53705, USA
| | - Ran Zhang
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53705, USA
| | - Ke Li
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53705, USA.,Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53705, USA
| | - Guang-Hong Chen
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53705, USA.,Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53705, USA
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Chen J, Zhu J, Li Z, Shi W, Zhang Q, Hu Z, Zheng H, Liang D, Ge Y. Automatic image-domain Moiré artifact reduction method in grating-based x-ray interferometry imaging. Phys Med Biol 2019; 64:195013. [PMID: 31422959 DOI: 10.1088/1361-6560/ab3c34] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
In this study, we propose to remove Moiré image artifact induced by system instabilities in grating-based x-ray interferometry imaging using convolutional neural network (CNN) technique. This method reduces Moiré image artifact in image-domain via a learned image post-processing procedure, rather than developing signal retrieval optimization algorithms to minimize the inconsistencies between acquired phase stepping data and assumed signal model. To achieve this aim, we suggested to train the CNN network using dataset synthesized from both natural images and experimentally acquired Moiré artifact-only images. In particular, a novel approach is developed to generate a large number of various high quality Moiré artifact-only images from finite groups of experimental phase stepping data. Both numerical and experimental results demonstrate that the developed CNN method is able to effectively remove the undesired Moiré image artifact. As a result, the image quality of a practical grating-based x-ray interferometry system can be greatly improved.
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Affiliation(s)
- Jianwei Chen
- Research Center for Medical Artificial Intelligence, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong 518055, People's Republic of China. Equal contributions to this work and all are considered as the first authors
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Li X, Gao H, Chen Z, Zhang L, Zhu X, Wang S, Peng W. A comparative study of information retrieval in grating-based x-ray phase-contrast imaging. ACTA ACUST UNITED AC 2019; 64:125010. [DOI: 10.1088/1361-6560/ab0d5a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Wang Z, Ren K, Shi X, Liu D, Wu Z, Gao K. Technical Note: Single-shot phase retrieval method for synchrotron-based high-energy x-ray grating interferometry. Med Phys 2019; 46:1317-1322. [DOI: 10.1002/mp.13399] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 11/20/2018] [Accepted: 01/18/2019] [Indexed: 01/31/2023] Open
Affiliation(s)
- Zhili Wang
- School of Electronic Science & Applied Physics; Hefei University of Technology; Hefei 230009 China
- Beijing Advanced Innovation Center for Imaging Technology; Capital Normal University; Beijing 100048 People's Republic of China
| | - Kun Ren
- School of Electronic Science & Applied Physics; Hefei University of Technology; Hefei 230009 China
| | - Xiaomin Shi
- School of Electronic Science & Applied Physics; Hefei University of Technology; Hefei 230009 China
| | - Dalin Liu
- School of Electronic Science & Applied Physics; Hefei University of Technology; Hefei 230009 China
| | - Zhao Wu
- National Synchrotron Radiation Laboratory University of Science and Technology of China; 230029 Hefei China
| | - Kun Gao
- National Synchrotron Radiation Laboratory University of Science and Technology of China; 230029 Hefei China
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Fu J, Shi X, Guo W, Peng P. Fast X-ray Differential Phase Contrast Imaging with One Exposure and without Movements. Sci Rep 2019; 9:1113. [PMID: 30718674 DOI: 10.1038/s41598-018-37687-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 12/12/2018] [Indexed: 11/08/2022] Open
Abstract
Grating interferometry X-ray differential phase contrast imaging (GI-XDPCI) has provided enhanced imaging contrast and attracted more and more interests. Currently the low imaging efficiency and increased dose remain to be the bottlenecks in the engineering applications of GI-XDPCI. Different from the widely-used X-ray absorption contrast imaging (XACI) found in hospitals and factories, GI-XDPCI involves a grating stepping procedure that is time-consuming and leads to a significantly increased X-ray exposure time. In this paper, we report a fast GI-XDPCI method without movements by designing a new absorption grating. There is no grating stepping in this approach, and all components remain stationary during the imaging. Three kinds of imaging contrasts are provided with greatly reduced time. This work is comprised of a numerical study of the method and its verification using a sub-set of the dataset measured with a standard GI-XDPCI system at the beam line BL13W1 of the Shanghai Synchrotron Radiation Facility (SSRF). These results have validated the presented method.
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17
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Wang Z, Ren K, Shi X, Ren Y, Gao K, Wu Z. Single-image phase retrieval for hard X-ray grating interferometry. J Synchrotron Radiat 2019; 26:215-219. [PMID: 30655487 DOI: 10.1107/s1600577518016727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Accepted: 11/24/2018] [Indexed: 06/09/2023]
Abstract
A single-image method is proposed for quantitative phase retrieval in hard X-ray grating interferometry. This novel method assumes a quasi-homogeneous sample, with a constant ratio between the real and imaginary parts of its complex refractive index. The method is first theoretically derived and presented, and then validated by synchrotron radiation experiments. Compared with the phase-stepping method, the presented approach abandons grating scanning and multiple image acquisition, and is therefore advantageous in terms of its simplified acquisition procedure and reduced data-collection times, which are especially important for applications such as in vivo imaging and phase tomography. Moreover, the sample's phase image, instead of its first derivative, is directly retrieved. In particular, the stripe artifacts encountered in the integrated phase images are significantly suppressed. The improved quality of the retrieved phase images can be beneficial for image interpretation and subsequent processing. Owing to its requirement for a single image and its robustness against noise, the present method is expected to find use in potential investigations in diverse applications.
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Affiliation(s)
- Zhili Wang
- School of Electronic Science and Applied Physics, Hefei University of Technology, Anhui 230009, People's Republic of China
| | - Kun Ren
- School of Electronic Science and Applied Physics, Hefei University of Technology, Anhui 230009, People's Republic of China
| | - Xiaomin Shi
- School of Electronic Science and Applied Physics, Hefei University of Technology, Anhui 230009, People's Republic of China
| | - Yuqi Ren
- Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204, People's Republic of China
| | - Kun Gao
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Anhui 230026, People's Republic of China
| | - Zhao Wu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Anhui 230026, People's Republic of China
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18
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Li X, Chen Z, Zhang L, Zhu X, Wang S, Peng W. Quantitative characterization of ex vivo breast tissue via x-ray phase-contrast tomography. J Xray Sci Technol 2019; 27:503-516. [PMID: 30958320 DOI: 10.3233/xst-180453] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
BACKGROUND Grating-based X-ray phase-contrast imaging (GPCI) has received growing interests in recent years due to its high capability of visualizing soft tissue. Breast imaging is one of the most promising candidates for the first clinical application of this imaging modality. OBJECTIVE In this work, quantitative breast tissue characterization based on GPCI computed tomography (CT) is investigated with a laboratory X-ray tube through a comparison between attenuation-based CT images and phase-contrast CT images. METHODS The Hounsfield units (HU) scale was introduced to phase-contrast images due to its wide application in clinical medicine. In this work, instead of water, plastic cylinders composed of polyethylene terephthalate (PET) was treated as the calibration material. An alternative test-retest reliability (TRR) was presented to evaluate the repeatability of GPCI. Comparison between attenuation-based CT imaging and GPCI CT imaging was operated with the use of statistical analysis methods like histograms and receiver operating characteristic (ROC) curves. RESULTS The determined mean TRR related to cylinders is slightly larger in phase-contrast imaging (0.93) than that in attenuation-based imaging (0.89). With respect to distinguishing breast tissues, the AUC (area under curve) values of ROC curves of phase-contrast images are higher than that of attenuation-based images. CONCLUSIONS An ex vivo study of GPCI shows that it is a stable imaging modality for visualizing the breast tissue with good repeatability, and that it could be of potential for the diagnosis of breast cancer as well.
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Affiliation(s)
- Xinbin Li
- Department of Engineering Physics, Tsinghua University, Haidian District, Beijing, China
- Key Laboratory of Particle & Radiation Imaging (Tsinghua University) of Ministry of Education, Haidian District, Beijing, China
| | - Zhiqiang Chen
- Department of Engineering Physics, Tsinghua University, Haidian District, Beijing, China
- Key Laboratory of Particle & Radiation Imaging (Tsinghua University) of Ministry of Education, Haidian District, Beijing, China
| | - Li Zhang
- Department of Engineering Physics, Tsinghua University, Haidian District, Beijing, China
- Key Laboratory of Particle & Radiation Imaging (Tsinghua University) of Ministry of Education, Haidian District, Beijing, China
| | - Xiaohua Zhu
- Department of Engineering Physics, Tsinghua University, Haidian District, Beijing, China
- Key Laboratory of Particle & Radiation Imaging (Tsinghua University) of Ministry of Education, Haidian District, Beijing, China
| | - Shengping Wang
- Fudan University Shanghai Cancer Center, 270 Dongan Road, Xuhui District, Shanghai, China
| | - Weijun Peng
- Fudan University Shanghai Cancer Center, 270 Dongan Road, Xuhui District, Shanghai, China
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19
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Lee H, Lim H, Jeon D, Park C, Lee D, Cho H, Seo C, Kim K, Kim G, Park S, Kang S, Park J, Kim W, Lim Y, Woo T. Eliminating artifacts in single-grid phase-contrast x-ray imaging for improving image quality. Comput Biol Med 2018; 97:74-82. [DOI: 10.1016/j.compbiomed.2018.04.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 04/03/2018] [Accepted: 04/19/2018] [Indexed: 10/17/2022]
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20
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Hauke C, Bartl P, Leghissa M, Ritschl L, Sutter SM, Weber T, Zeidler J, Freudenberger J, Mertelmeier T, Radicke M, Michel T, Anton G, Meinel FG, Baehr A, Auweter S, Bondesson D, Gaass T, Dinkel J, Reiser M, Hellbach K. A preclinical Talbot-Lau prototype for x-ray dark-field imaging of human-sized objects. Med Phys 2018; 45:2565-2571. [DOI: 10.1002/mp.12889] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 03/09/2018] [Accepted: 03/09/2018] [Indexed: 12/13/2022] Open
Affiliation(s)
- C. Hauke
- Siemens Healthcare GmbH; 91301 Forchheim Germany
- Erlangen Centre for Astroparticle Physics; FAU Erlangen-Nuremberg; 91058 Erlangen Germany
| | - P. Bartl
- Siemens Healthcare GmbH; 91301 Forchheim Germany
| | - M. Leghissa
- Siemens Healthcare GmbH; 91301 Forchheim Germany
| | - L. Ritschl
- Siemens Healthcare GmbH; 91301 Forchheim Germany
| | - S. M. Sutter
- Siemens Healthcare GmbH; 91301 Forchheim Germany
| | - T. Weber
- Siemens Healthcare GmbH; 91301 Forchheim Germany
| | - J. Zeidler
- Siemens Healthcare GmbH; 91301 Forchheim Germany
| | | | | | - M. Radicke
- Siemens Healthcare GmbH; 91301 Forchheim Germany
| | - T. Michel
- Erlangen Centre for Astroparticle Physics; FAU Erlangen-Nuremberg; 91058 Erlangen Germany
| | - G. Anton
- Erlangen Centre for Astroparticle Physics; FAU Erlangen-Nuremberg; 91058 Erlangen Germany
| | - F. G. Meinel
- Department of Diagnostic and Interventional Radiology; University of Rostock Medical Center; 18057 Rostock Germany
| | - A. Baehr
- Department of Veterinary Science; LMU Munich; 85764 Oberschleissheim Germany
| | - S. Auweter
- Department of Radiology; University Hospital; LMU Munich; 80336 Munich Germany
| | - D. Bondesson
- Department of Radiology; University Hospital; LMU Munich; 80336 Munich Germany
| | - T. Gaass
- Department of Radiology; University Hospital; LMU Munich; 80336 Munich Germany
| | - J. Dinkel
- Department of Radiology; University Hospital; LMU Munich; 80336 Munich Germany
| | - M. Reiser
- Department of Radiology; University Hospital; LMU Munich; 80336 Munich Germany
| | - K. Hellbach
- Department of Radiology; University Hospital; LMU Munich; 80336 Munich Germany
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21
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Li X, Gao H, Chen Z, Zhang L, Zhu X, Wang S, Peng W. Diagnosis of breast cancer based on microcalcifications using grating-based phase contrast CT. Eur Radiol 2018; 28:3742-50. [DOI: 10.1007/s00330-017-5158-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [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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22
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Sung Y, Gupta R, Nelson B, Leng S, McCollough CH, Graves WS. Phase-contrast imaging with a compact x-ray light source: system design. J Med Imaging (Bellingham) 2017; 4:043503. [PMID: 29201939 DOI: 10.1117/1.jmi.4.4.043503] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 11/06/2017] [Indexed: 11/14/2022] Open
Abstract
X-ray phase-contrast imaging (XPCI) overcomes the problem of low contrast between different soft tissues achieved in conventional x-ray imaging by introducing x-ray phase as an additional contrast mechanism. This work describes a compact x-ray light source (CXLS) and compares, via simulations, the high quality XPCI results that can be produced from this source to those produced using a microfocus x-ray source. The simulation framework is first validated using an image acquired with a microfocus-source, propagation-based XPCI (PB-XPCI) system. The phase contrast for a water sphere simulating a simple cyst submersed in muscle is evaluated and the evolution of PB-XPCI signal as the object to detector distance is increased is demonstrated. The proposed design of a PB-XPCI system using the CXLS is described and simulated images of a coronary artery compared between CXLS and microfocus source PB-XPCI systems. To generate images with similar noise levels, a microfocus source would require a 3000 times longer exposure than would the CXLS. We conclude that CXLS technology has the potential to provide high-quality XPCI in a medical environment using extremely short exposure times relative to microfocus source approaches.
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Affiliation(s)
- Yongjin Sung
- University of Wisconsin-Milwaukee, College of Engineering and Applied Science, Milwaukee, Wisconsin, United States
| | - Rajiv Gupta
- Massachusetts General Hospital, Department of Radiology, Boston, Massachusetts, United States
| | - Brandon Nelson
- Mayo Clinic, Department of Radiology, Rochester, Minnesota, United States
| | - Shuai Leng
- Mayo Clinic, Department of Radiology, Rochester, Minnesota, United States
| | | | - William S Graves
- Arizona State University, Department of Physics, Tempe, Arizona, United States
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23
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Abstract
Dark-field imaging is a scattering-based X-ray imaging method that can be performed with laboratory X-ray tubes. The possibility to obtain information about unresolvable structures has already seen a lot of interest for both medical and material science applications. Unlike conventional X-ray attenuation, orientation dependent changes of the dark-field signal can be used to reveal microscopic structural orientation. To date, reconstruction of the three-dimensional dark-field signal requires dedicated, highly complex algorithms and specialized acquisition hardware. This severely hinders the possible application of orientation-dependent dark-field tomography. In this paper, we show that it is possible to perform this kind of dark-field tomography with common Talbot-Lau interferometer setups by reducing the reconstruction to several smaller independent problems. This allows for the reconstruction to be performed with commercially available software and our findings will therefore help pave the way for a straightforward implementation of orientation-dependent dark-field tomography.
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24
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Ji X, Ge Y, Zhang R, Li K, Chen GH. Studies of signal estimation bias in grating-based x-ray multicontrast imaging. Med Phys 2017; 44:2453-2465. [PMID: 28339107 DOI: 10.1002/mp.12235] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Revised: 03/08/2017] [Accepted: 03/12/2017] [Indexed: 11/08/2022] Open
Abstract
PURPOSE In grating-based x-ray multi-contrast imaging, signals of three contrast mechanisms-absorption contrast, differential phase contrast (DPC), and dark-field contrast-can be estimated from the same set of acquired data. The estimated signals, N0 (related to absorption), N1 (related to dark-field), and φ (related to DPC) may be intrinsically biased. However, it is yet unclear how large these biases are and how the data acquisition parameters affect the biases in the extracted signals. The purpose of this paper was to address these questions. METHODS The biases of the extracted signals (i.e., N0 , N1 and φ) were theoretically studied for a well-known signal estimation method. Experimental data acquired from a grating-based x-ray multi-contrast benchtop imaging system with a photon counting detector were used to validate the theoretical results for the signal biases of the three contrast mechanisms. RESULTS Both theoretical and experimental studies showed the following results: (1) The bias of signal estimation for the absorption contrast signal is zero; (2) The bias of signal estimation for N1 is inversely proportional to the number of phase steps and to the average fringe visibility of the grating interferometer, but the ratio between the bias and the signal level (i.e., the relative bias) is independent of the number of phase steps; (3) The bias of signal estimation for φ depends on the mean DPC signal level, the total exposure level of the multi-contrast data acquisition, and the mean fringe visibility of the interferometer. CONCLUSIONS In grating-based x-ray multi-contrast imaging, the estimated absorption contrast signal is unbiased; the estimated dark-field contrast signal is biased, but the relative bias is only dependent on the mean fringe visibility of the interferometer and the exposure level. The estimated DPC signal may be biased, and the bias level depends on the mean signal level, the exposure level, and the interferometer performance.
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Affiliation(s)
- Xu Ji
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Yongshuai Ge
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Ran Zhang
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Ke Li
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA.,Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Guang-Hong Chen
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA.,Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
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25
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Ge Y, Zhang R, Li K, Chen GH. Improving radiation dose efficiency of X-ray differential phase contrast imaging using an energy-resolving grating interferometer and a novel rank constraint. Opt Express 2016; 24:12955-12968. [PMID: 27410315 PMCID: PMC5025210 DOI: 10.1364/oe.24.012955] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 05/23/2016] [Accepted: 05/24/2016] [Indexed: 06/06/2023]
Abstract
In this paper, a novel method was developed to improve the radiation dose efficiency, viz., contrast to noise ratio normalized by dose (CNRD), of the grating-based X-ray differential phase contrast (DPC) imaging system that is integrated with an energy-resolving photon counting detector. The method exploits the low-dimensionality of the spatial-spectral DPC image matrix acquired from different energy windows. A low rank approximation of the spatial-spectral image matrix was developed to reduce image noise while retaining the DPC signal accuracy for every energy window. Numerical simulations and experimental phantom studies have been performed to validate the proposed method by showing noise reduction and CNRD improvement for each energy window.
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Affiliation(s)
- Yongshuai Ge
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI,
USA
| | - Ran Zhang
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI,
USA
| | - Ke Li
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI,
USA
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI,
USA
| | - Guang-Hong Chen
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI,
USA
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI,
USA
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26
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Endrizzi M, Astolfo A, Vittoria FA, Millard TP, Olivo A. Asymmetric masks for laboratory-based X-ray phase-contrast imaging with edge illumination. Sci Rep 2016; 6:25466. [PMID: 27145924 DOI: 10.1038/srep25466] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 04/18/2016] [Indexed: 02/08/2023] Open
Abstract
We report on an asymmetric mask concept that enables X-ray phase-contrast imaging without requiring any movement in the system during data acquisition. The method is compatible with laboratory equipment, namely a commercial detector and a rotating anode tube. The only motion required is that of the object under investigation which is scanned through the imaging system. Two proof-of-principle optical elements were designed, fabricated and experimentally tested. Quantitative measurements on samples of known shape and composition were compared to theory with good agreement. The method is capable of measuring the attenuation, refraction and (ultra-small-angle) X-ray scattering, does not have coherence requirements and naturally adapts to all those situations in which the X-ray image is obtained by scanning a sample through the imaging system.
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27
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Marschner M, Willner M, Potdevin G, Fehringer A, Noël PB, Pfeiffer F, Herzen J. Helical X-ray phase-contrast computed tomography without phase stepping. Sci Rep 2016; 6:23953. [PMID: 27052368 PMCID: PMC4823776 DOI: 10.1038/srep23953] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 03/17/2016] [Indexed: 01/15/2023] Open
Abstract
X-ray phase-contrast computed tomography (PCCT) using grating interferometry provides enhanced soft-tissue contrast. The possibility to use standard polychromatic laboratory sources enables an implementation into a clinical setting. Thus, PCCT has gained significant attention in recent years. However, phase-contrast CT scans still require significantly increased measurement times in comparison to conventional attenuation-based CT imaging. This is mainly due to a time-consuming stepping of a grating, which is necessary for an accurate retrieval of the phase information. In this paper, we demonstrate a novel scan technique, which directly allows the determination of the phase signal without a phase-stepping procedure. The presented work is based on moiré fringe scanning, which allows fast data acquisition in radiographic applications such as mammography or in-line product analysis. Here, we demonstrate its extension to tomography enabling a continuous helical sample rotation as routinely performed in clinical CT systems. Compared to standard phase-stepping techniques, the proposed helical fringe-scanning procedure enables faster measurements, an extended field of view and relaxes the stability requirements of the system, since the gratings remain stationary. Finally, our approach exceeds previously introduced methods by not relying on spatial interpolation to acquire the phase-contrast signal.
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Affiliation(s)
- M Marschner
- Lehrstuhl für Biomedizinische Physik, Physik-Department &Institut für Medizintechnik, Technische Universität München, 85748 Garching, Germany
| | - M Willner
- Lehrstuhl für Biomedizinische Physik, Physik-Department &Institut für Medizintechnik, Technische Universität München, 85748 Garching, Germany
| | - G Potdevin
- Lehrstuhl für Biomedizinische Physik, Physik-Department &Institut für Medizintechnik, Technische Universität München, 85748 Garching, Germany
| | - A Fehringer
- Lehrstuhl für Biomedizinische Physik, Physik-Department &Institut für Medizintechnik, Technische Universität München, 85748 Garching, Germany
| | - P B Noël
- Lehrstuhl für Biomedizinische Physik, Physik-Department &Institut für Medizintechnik, Technische Universität München, 85748 Garching, Germany.,Institut für diagnostische und interventionelle Radiologie, Klinikum rechts der Isar, Technische Universität München, 81675 München, Germany
| | - F Pfeiffer
- Lehrstuhl für Biomedizinische Physik, Physik-Department &Institut für Medizintechnik, Technische Universität München, 85748 Garching, Germany.,Institut für diagnostische und interventionelle Radiologie, Klinikum rechts der Isar, Technische Universität München, 81675 München, Germany
| | - J Herzen
- Lehrstuhl für Biomedizinische Physik, Physik-Department &Institut für Medizintechnik, Technische Universität München, 85748 Garching, Germany
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28
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Li P, Zhang K, Bao Y, Ren Y, Ju Z, Wang Y, He Q, Zhu Z, Huang W, Yuan Q, Zhu P. Angular signal radiography. Opt Express 2016; 24:5829-5845. [PMID: 27136780 DOI: 10.1364/oe.24.005829] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Microscopy techniques using visible photons, x-rays, neutrons, and electrons have made remarkable impact in many scientific disciplines. The microscopic data can often be expressed as the convolution of the spatial distribution of certain properties of the specimens and the inherent response function of the imaging system. The x-ray grating interferometer (XGI), which is sensitive to the deviation angle of the incoming x-rays, has attracted significant attention in the past years due to its capability in achieving x-ray phase contrast imaging with low brilliance source. However, the comprehensive and analytical theoretical framework is yet to be presented. Herein, we propose a theoretical framework termed angular signal radiography (ASR) to describe the imaging process of the XGI system in a classical, comprehensive and analytical manner. We demonstrated, by means of theoretical deduction and synchrotron based experiments, that the spatial distribution of specimens' physical properties, including absorption, refraction and scattering, can be extracted by ASR in XGI. Implementation of ASR in XGI offers advantages such as simplified phase retrieval algorithm, reduced overall radiation dose, and improved image acquisition speed. These advantages, as well as the limitations of the proposed method, are systematically investigated in this paper.
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29
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Zanette I, Zdora MC, Zhou T, Burvall A, Larsson DH, Thibault P, Hertz HM, Pfeiffer F. X-ray microtomography using correlation of near-field speckles for material characterization. Proc Natl Acad Sci U S A 2015; 112:12569-73. [PMID: 26424447 DOI: 10.1073/pnas.1502828112] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
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.
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30
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Sunaguchi N, Yuasa T, Hirano SI, Gupta R, Ando M. In Vitro Validation of an Artefact Suppression Algorithm in X-Ray Phase-Contrast Computed Tomography. PLoS One 2015; 10:e0135654. [PMID: 26295713 PMCID: PMC4546599 DOI: 10.1371/journal.pone.0135654] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Accepted: 07/23/2015] [Indexed: 11/18/2022] Open
Abstract
X-ray phase-contrast tomography can significantly increase the contrast-resolution of conventional attenuation-contrast imaging, especially for soft-tissue structures that have very similar attenuation. Just as in attenuation-based tomography, phase contrast tomography requires a linear dependence of aggregate beam direction on the incremental direction alteration caused by individual voxels along the path of the X-ray beam. Dense objects such as calcifications in biological specimens violate this condition. There are extensive beam deflection artefacts in the vicinity of such structures because they result in large distortion of wave front due to the large difference of refractive index; for such large changes in beam direction, the transmittance of the silicon analyzer crystal saturates and is no longer linearly dependent on the angle of refraction. This paper describes a method by which these effects can be overcome and excellent soft-tissue contrast of phase tomography can be preserved in the vicinity of such artefact-producing structures.
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MESH Headings
- Algorithms
- Animals
- Arthritis, Experimental/diagnostic imaging
- Arthritis, Experimental/pathology
- Arthritis, Rheumatoid/diagnostic imaging
- Arthritis, Rheumatoid/pathology
- Artifacts
- Atherosclerosis/diagnostic imaging
- Atherosclerosis/pathology
- Coronary Vessels/diagnostic imaging
- Coronary Vessels/pathology
- Disease Models, Animal
- Female
- Humans
- Image Processing, Computer-Assisted/methods
- Plaque, Atherosclerotic/diagnostic imaging
- Plaque, Atherosclerotic/pathology
- Rats
- Rats, Inbred Lew
- Refractometry
- Tomography, X-Ray Computed/instrumentation
- Tomography, X-Ray Computed/methods
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Affiliation(s)
- Naoki Sunaguchi
- Graduate School of Engineering, Gunma University, Kiryu, Gunma, Japan
- * E-mail:
| | - Tetsuya Yuasa
- Graduate School of Engineering and Science, Yamagata University, Yonezawa, Yamagata, Japan
| | - Shin-ichi Hirano
- Mercian Cleantec Corporation, Fujisawa, Kanagawa, Japan
- MiZ Corporation, Kamakura, Kanagawa, Japan
| | - Rajiv Gupta
- Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Masami Ando
- Research Institute for Science and Technology, Tokyo University of Science, Noda, Chiba, Japan
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Sung Y, Segars WP, Pan A, Ando M, Sheppard CJR, Gupta R. Realistic wave-optics simulation of X-ray phase-contrast imaging at a human scale. Sci Rep 2015; 5:12011. [PMID: 26169570 PMCID: PMC4500945 DOI: 10.1038/srep12011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 06/11/2015] [Indexed: 01/31/2023] Open
Abstract
X-ray phase-contrast imaging (XPCI) can dramatically improve soft tissue contrast in X-ray medical imaging. Despite worldwide efforts to develop novel XPCI systems, a numerical framework to rigorously predict the performance of a clinical XPCI system at a human scale is not yet available. We have developed such a tool by combining a numerical anthropomorphic phantom defined with non-uniform rational B-splines (NURBS) and a wave optics-based simulator that can accurately capture the phase-contrast signal from a human-scaled numerical phantom. Using a synchrotron-based, high-performance XPCI system, we provide qualitative comparison between simulated and experimental images. Our tool can be used to simulate the performance of XPCI on various disease entities and compare proposed XPCI systems in an unbiased manner.
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Affiliation(s)
- Yongjin Sung
- Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114, USA
| | - W Paul Segars
- Department of Radiology, Duke University, Durham, North Carolina 27705, USA
| | - Adam Pan
- Harvard-MIT Division of Health Sciences and Technology, Cambridge, Massachusetts 02139, USA
| | - Masami Ando
- The Research Institute for Science and Technology, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | | | - Rajiv Gupta
- Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114, USA
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Du Y, Liu X, Huang J, Lei Y, Zhao Z, Lin D, Guo J, Li J, Niu H. Sampling grating approach for X-ray differential phase contrast imaging. Opt Express 2015; 23:12712-12719. [PMID: 26074525 DOI: 10.1364/oe.23.012712] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Grating-based X-ray differential phase contrast imaging (GDPCI) typically employs the phase-stepping technique to extract an object's phase information. This method requires heavy radiation dosage and is time consuming. Another potential approach is the reverse projection (RP) method, which, however, relies on a synchrotron radiation source to obtain highly sensitive differential phase contrast(DPC) signal. Here, we present an alternative approach that enables the RP method to be used with a conventional X-ray source and substantially improves the sensitivity of the DPC signal by replacing the analyzer grating of the GDPCI with a sampling grating. This development represents a significant step towards obtaining fast and low-dosage DPC images in medical, biological, and industrial applications.
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Harmon KJ, Miao H, Gomella AA, Bennett EE, Foster BA, Bhandarkar P, Wen H. Motionless electromagnetic phase stepping versus mechanical phase stepping in x-ray phase-contrast imaging with a compact source. Phys Med Biol 2015; 60:3031-43. [PMID: 25803511 DOI: 10.1088/0031-9155/60/8/3031] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
X-ray phase contrast imaging based on grating interferometers detects the refractive index distribution of an object without relying on radiation attenuation, thereby having the potential for reduced radiation absorption. These techniques belong to the broader category of optical wavefront measurement, which requires stepping the phase of the interference pattern to obtain a pixel-wise map of the phase distortion of the wavefront. While phase stepping traditionally involves mechanical scanning of a grating or mirror, we developed electromagnetic phase stepping (EPS) for imaging with compact sources to obviate the need for mechanical movement. In EPS a solenoid coil is placed outside the x-ray tube to shift its focal spot with a magnetic field, causing a relative movement between the projection of the sample and the interference pattern in the image. Here we present two embodiments of this method. We verified experimentally that electromagnetic and mechanical phase stepping give the same results and attain the same signal-to-noise ratios under the same radiation dose. We found that the relative changes of interference fringe visibility were within 3.0% when the x-ray focal spot was shifted by up to 1.0 mm in either direction. We conclude that when using x-ray tube sources, EPS is an effective means of phase stepping without the need for mechanical movement.
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Affiliation(s)
- Katherine J Harmon
- Imaging Physics Laboratory, Biochemistry and Biophysics Center, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
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Garrett J, Ge Y, Li K, Chen GH. Anatomical background noise power spectrum in differential phase contrast and dark field contrast mammograms. Med Phys 2014; 41:120701. [DOI: 10.1118/1.4901313] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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