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Alvarez-Padilla FJ, Flores-Nunez JL, Alvarez-Padilla JR, Gonzalez FJ, Oceguera-Villanueva A, Gutierrez-Quiroz BA. Breast segmentation in infrared thermography from characteristical inframammary shape. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2024; 40:e3843. [PMID: 38963037 DOI: 10.1002/cnm.3843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 05/14/2024] [Accepted: 06/18/2024] [Indexed: 07/05/2024]
Abstract
Infrared thermography is gaining relevance in breast cancer assessment. For this purpose, breast segmentation in thermograms is an important task for performing automatic image analysis and detecting possible temperature changes that indicate the presence of malignancy. However, it is not a simple task since the breast limit borders, especially the top borders, often have low contrast, making it difficult to isolate the breast area. Several algorithms have been proposed for breast segmentation, but these highly depend on the contrast at the lower breast borders and on filtering algorithms to remove false edges. This work focuses on taking advantage of the distinctive inframammary shape to simplify the definition of the lower breast border, regardless of the contrast level, which indeed also provides a strong anatomical reference to support the definition of the poorly marked upper boundary of the breasts, which has been one of the major challenges in the literature. In order to demonstrate viability of the proposed technique for an automatic breast segmentation, we applied it to a database with 180 thermograms and compared their results with those reported by others in the literature. We found that our approach achieved a high performance, in terms of Intersection over Union of 0.934, even higher than that reported by artificial intelligence algorithms. The performance is invariant to breast sizes and thermal contrast of the images.
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Affiliation(s)
| | - Jorge L Flores-Nunez
- Department of Translational Bioengineering, Universidad de Guadalajara, Jalisco, Mexico
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2
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Pandey PK, Wang S, Sun L, Xing L, Xiang L. Model-Based 3-D X-Ray Induced Acoustic Computerized Tomography. IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES 2023; 7:532-543. [PMID: 38046375 PMCID: PMC10691826 DOI: 10.1109/trpms.2023.3238017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
X-ray-induced acoustic (XA) computerized tomography (XACT) is an evolving imaging technique that aims to reconstruct the X-ray energy deposition from XA measurements. Main challenges in XACT are the poor signal-to-noise ratio and limited field-of-view, which cause artifacts in the images. We demonstrate the efficacy of model-based (MB) algorithms for three-dimensional XACT and compare with the traditional algorithms. The MB algorithm is based on iterative, matrix-free approach for regularized-least-squares minimization corresponding to XACT. The matrix-free-LSQR (MF-LSQR) and the non-iterative model-backprojection (MBP) reconstructions were evaluated and compared with universal backprojection (UBP), time-reversal (TR) and fast-Fourier transform (FFT)-based reconstructions for numerical and experimental XACT datasets. The results demonstrate the capability of MF-LSQR algorithm to reduce noisy artifacts thus yielding better reconstructions. MBP and MF-LSQR algorithms perform particularly well with the experimental XACT dataset, where noise in signals significantly affects the reconstruction of the target in UBP and FFT-based reconstructions. The TR reconstruction for experimental XACT are comparable to MF-LSQR, but takes thrice as much time and filters the frequency components greater than maximum frequency supported by the grid, resulting loss of resolution. The MB algorithms are able to overcome the challenges in XACT and hence are vital for the clinical translation of XACT.
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Affiliation(s)
- Prabodh Kumar Pandey
- Department of Radiological Sciences, University of California, Irvine, CA, 92697, USA
| | - Siqi Wang
- Department of Biomedical Engineering, University of California, Irvine, CA 92617, USA
| | - Leshan Sun
- Department of Biomedical Engineering, University of California, Irvine, CA 92617, USA
| | - Lei Xing
- Department of Radiological Sciences, University of California, Irvine, CA, 92697, USA.; Department of Biomedical Engineering, University of California, Irvine, CA 92617, USA.; Beckman Laser Institute, University of California, Irvine, CA 92612, USA
| | - Liangzhong Xiang
- Division of Medical Physics, Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA,94305, USA
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Barbagianni MS, Gouletsou PG. Modern Imaging Techniques in the Study and Disease Diagnosis of the Mammary Glands of Animals. Vet Sci 2023; 10:vetsci10020083. [PMID: 36851387 PMCID: PMC9965774 DOI: 10.3390/vetsci10020083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 01/12/2023] [Accepted: 01/20/2023] [Indexed: 01/25/2023] Open
Abstract
The study of the structure and function of the animals' mammary glands is of key importance, as it reveals pathological processes at their onset, thus contributing to their immediate treatment. The most frequently studied mammary diseases are mastitis in cows and ewes and mammary tumours in dogs and cats. Various imaging techniques such as computed tomography, positron emission tomography, magnetic resonance imaging, and ultrasonographic techniques (Doppler, contrast-enchanced, three-dimensional and elastography) are available and can be applied in research or clinical practice in order to evaluate possible abnormalities in mammary glands, as well as to assist in the differential diagnosis. In this review, the above imaging technologies are described, and the perspectives of each method are highlighted. It is inferred that ultrasonographic modalities are the most frequently used imaging techniques for the diagnosis of clinical or subclinical mastitis and treatment guidance on a farm. In companion animals, a combination of imaging techniques should be applied for a more accurate diagnosis of mammary tumours. In any case, the confirmation of the diagnosis is provided by laboratory techniques.
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Pandey PK, Wang S, Aggrawal HO, Bjegovic K, Boucher S, Xiang L. Model-Based X-Ray-Induced Acoustic Computed Tomography. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2021; 68:3560-3569. [PMID: 34310297 PMCID: PMC8739265 DOI: 10.1109/tuffc.2021.3098501] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
X-ray-induced acoustic computed tomography (XACT) provides X-ray absorption-based contrast with acoustic detection. For its clinical translation, XACT imaging often has a limited field of view. This can result in image artifacts and overall loss of quantification accuracy. In this article, we aim to demonstrate model-based XACT image reconstruction to address these problems. An efficient matrix-free implementation of the regularized LSQR (MF-LSQR)-based minimization scheme and a noniterative model back-projection (MBP) scheme for computing XACT reconstructions have been demonstrated in this article. The proposed algorithms have been numerically validated and then used to perform reconstructions from experimental measurements obtained from an XACT setup. While the commonly used back-projection (BP) algorithm produces limited-view and noisy artifacts in the region of interest (ROI), model-based LSQR minimization overcomes these issues. The model-based algorithms also reduce the ring artifacts caused due to the nonuniformity response of the multichannel data acquisition. Using the model-based reconstruction algorithms, we are able to obtain reasonable XACT reconstructions for acoustic measurements of up to 120° view. Although the MBP is more efficient than the model-based LSQR algorithm, it provides only the structural information of the ROI. Overall, it has been demonstrated that the model-based image reconstruction yields better image quality for XACT than the standard BP. Moreover, the combination of model-based image reconstruction with different regularization methods can solve the limited-view problem for XACT imaging (in many realistic cases where the full-view dataset is unavailable), and hence pave the way for future clinical translation.
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Zhu Y, O'Connell AM, Ma Y, Liu A, Li H, Zhang Y, Zhang X, Ye Z. Dedicated breast CT: state of the art-Part II. Clinical application and future outlook. Eur Radiol 2021; 32:2286-2300. [PMID: 34476564 DOI: 10.1007/s00330-021-08178-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 06/19/2021] [Accepted: 06/29/2021] [Indexed: 12/17/2022]
Abstract
Dedicated breast CT is being increasingly used for breast imaging. This technique provides images with no compression, removal of tissue overlap, rapid acquisition, and available simultaneous assessment of microcalcifications and contrast enhancement. In this second installment in a 2-part review, the current status of clinical applications and ongoing efforts to develop new imaging systems are discussed, with particular emphasis on how to achieve optimized practice including lesion detection and characterization, response to therapy monitoring, density assessment, intervention, and implant evaluation. The potential for future screening with breast CT is also addressed. KEY POINTS: • Dedicated breast CT is an emerging modality with enormous potential in the future of breast imaging by addressing numerous clinical needs from diagnosis to treatment. • Breast CT shows either noninferiority or superiority with mammography and numerical comparability to MRI after contrast administration in diagnostic statistics, demonstrates excellent performance in lesion characterization, density assessment, and intervention, and exhibits promise in implant evaluation, while potential application to breast cancer screening is still controversial. • New imaging modalities such as phase-contrast breast CT, spectral breast CT, and hybrid imaging are in the progress of R & D.
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Affiliation(s)
- Yueqiang Zhu
- Department of Radiology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Huan-Hu-Xi Road, Ti-Yuan-Bei, Hexi District, 300060, Tianjin, China
| | - Avice M O'Connell
- Department of Imaging Sciences, University of Rochester Medical Center, 601 Elmwood Avenue, Box 648, Rochester, NY, 14642, USA
| | - Yue Ma
- Department of Radiology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Huan-Hu-Xi Road, Ti-Yuan-Bei, Hexi District, 300060, Tianjin, China
| | - Aidi Liu
- Department of Radiology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Huan-Hu-Xi Road, Ti-Yuan-Bei, Hexi District, 300060, Tianjin, China
| | - Haijie Li
- Department of Radiology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Huan-Hu-Xi Road, Ti-Yuan-Bei, Hexi District, 300060, Tianjin, China
| | - Yuwei Zhang
- Department of Radiology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Huan-Hu-Xi Road, Ti-Yuan-Bei, Hexi District, 300060, Tianjin, China
| | - Xiaohua Zhang
- Koning Corporation, Lennox Tech Enterprise Center, 150 Lucius Gordon Drive, Suite 112, West Henrietta, NY, 14586, USA
| | - Zhaoxiang Ye
- Department of Radiology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Huan-Hu-Xi Road, Ti-Yuan-Bei, Hexi District, 300060, Tianjin, China.
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Recent advances in X-ray imaging of breast tissue: From two- to three-dimensional imaging. Phys Med 2020; 79:69-79. [PMID: 33171371 DOI: 10.1016/j.ejmp.2020.10.025] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2020] [Revised: 10/13/2020] [Accepted: 10/24/2020] [Indexed: 11/20/2022] Open
Abstract
Breast cancer is a globally widespread disease whose detection has already been significantly improved by the introduction of screening programs. Nevertheless, mammography suffers from low soft tissue contrast and the superposition of diagnostically relevant anatomical structures as well as from low values for sensitivity and specificity especially for dense breast tissue. In recent years, two techniques for X-ray breast imaging have been developed that bring advances for the early detection of breast cancer. Grating-based phase-contrast mammography is a new imaging technique that is able to provide three image modalities simultaneously (absorption-contrast, phase-contrast and dark-field signal). Thus, an enhanced detection and delineation of cancerous structures in the phase-contrast image and an improved visualization and characterization of microcalcifications in the dark-field image is possible. Furthermore, latest studies about this approach show that dose-compatible imaging with polychromatic X-ray sources is feasible. In order to additionally overcome the limitations of projection-based imaging, efforts were also made towards the development of breast computed tomography (BCT), which recently led to the first clinical installation of an absorption-based BCT system. Further research combining the benefits of both imaging technologies is currently in progress. This review article summarizes the latest advances in phase-contrast imaging for the female breast (projection-based and three-dimensional view) with special focus on possible clinical implementations in the future.
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Zhao C, Herbst M, Vogt S, Ritschl L, Kappler S, Siewerdsen JH, Zbijewski W. Cone-beam imaging with tilted rotation axis: Method and performance evaluation. Med Phys 2020; 47:3305-3320. [PMID: 32340069 DOI: 10.1002/mp.14209] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 02/26/2020] [Accepted: 04/13/2020] [Indexed: 01/07/2023] Open
Abstract
PURPOSE The recently introduced robotic x-ray systems provide the flexibility to acquire cone-beam computed tomography (CBCT) data using customized, application-specific source-detector trajectories. We exploit this capability to mitigate the effects of x-ray scatter and noise in CBCT imaging of weight-bearing foot and cervical spine (C-spine) using scan orbits with a tilted rotation axis. METHODS We used an advanced CBCT simulator implementing accurate models of x-ray scatter, primary attenuation, and noise to investigate the effects of the orbital tilt angle in upright foot and C-spine imaging. The system model was parameterized using a laboratory version of a three-dimensional (3D) robotic x-ray system (Multitom RAX, Siemens Healthineers). We considered a generalized tilted axis scan configuration, where the detector remained parallel to patient's long body axis during the acquisition, but the elevation of source and detector was changing. A modified Feldkamp-Davis-Kress (FDK) algorithm was developed for reconstruction in this configuration, which departs from the FDK assumption of a detector that is perpendicular to the scan plane. The simulated foot scans involved source-detector distance (SDD) of 1386 mm, orbital tilt angles ranging 10° to 40°, and 400 views at 1 mAs/view and 0.5° increment; the C-spine scans involved -25° to -45° tilt angles, SDD of 1090 mm, and 202 views at 1.3 mAs and 1° increment The imaging performance was assessed by projection-domain measurements of the scatter-to-primary ratio (SPR) and by reconstruction-domain measurements of contrast, noise and generalized contrast-to-noise ratio (gCNR, accounting for both image noise and background nonuniformity) of the metatarsals (foot imaging) and cervical vertebrae (spine imaging). The effects of scatter correction were also compared for horizontal and tilted scans using an ideal Monte Carlo (MC)-based scatter correction and a frame-by-frame mean scatter correction. RESULTS The proposed modified FDK, involving projection resampling, mitigated streak artifacts caused by the misalignment between the filtering direction and the detector rows. For foot imaging (no grids), an optimized 20° tilted orbit reduced the maximum SPR from ~1.5 in a horizontal scan to <0.5. The gCNR of the second metatarsal was enhanced twofold compared to a horizontal orbit. For the C-spine (with vertical grids), imaging with a tilted orbit avoided highly attenuating x-ray paths through the lower cervical vertebrae and shoulders. A -35° tilted orbit yielded improved image quality and visualization of the lower cervical spine: the SPR of lower cervical vertebrae was reduced from ~10 (horizontal orbit) to <6 (tilted orbit), and the gCNR for C5-C7 increased by a factor of 2. Furthermore, tilted orbits showed potential benefits over horizontal orbits by enabling scatter correction with a simple frame-by-frame mean correction without substantial increase in noise-induced artifacts after the correction. CONCLUSIONS Tilted scan trajectories, enabled by the emerging robotic x-ray system technology, were optimized for CBCT imaging of foot and cervical spine using an advanced simulation framework. The results demonstrated the potential advantages of tilted axis orbits in mitigation of scatter artifacts and improving contrast-to-noise ratio in CBCT reconstructions.
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Affiliation(s)
- Chumin Zhao
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, 21205, USA
| | | | | | | | | | - Jeffrey H Siewerdsen
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, 21205, USA.,Russell H. Morgan Department of Radiology, Johns Hopkins University, Baltimore, MD, 21287, USA
| | - Wojciech Zbijewski
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, 21205, USA
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Heck L, Eggl E, Grandl S, Dierolf M, Jud C, Günther B, Achterhold K, Mayr D, Gleich B, Hellerhoff K, Pfeiffer F, Herzen J. Dose and spatial resolution analysis of grating-based phase-contrast mammography using an inverse Compton x-ray source. J Med Imaging (Bellingham) 2020; 7:023505. [PMID: 32341937 PMCID: PMC7175026 DOI: 10.1117/1.jmi.7.2.023505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 04/06/2020] [Indexed: 11/14/2022] Open
Abstract
Purpose: Although the mortality rate of breast cancer was reduced with the introduction of screening mammography, many women undergo unnecessary subsequent examinations due to inconclusive diagnoses. Superposition of anatomical structures especially within dense breasts in conjunction with the inherently low soft tissue contrast of absorption images compromises image quality. This can be overcome by phase-contrast imaging. Approach: We analyze the spatial resolution of grating-based multimodal mammography using a mammographic phantom and one freshly dissected mastectomy specimen at an inverse Compton x-ray source. Here, the focus was on estimating the spatial resolution with the sample in the beam path and discussing benefits and drawbacks of the method used and the estimation of the mean glandular dose. Finally, the possibility of improving the spatial resolution is investigated by comparing monochromatic grating-based mammography with the standard one. Results: The spatial resolution is constant or also higher for the image acquired with monochromatic radiation and the contrast-to-noise ratio (CNR) is higher in our approach while the dose can be reduced by up to 20%. Conclusions: In summary, phase-contrast imaging helps to improve tumor detection by advanced diagnostic image quality. We demonstrate a higher spatial resolution for one mastectomy specimen and increased CNR at an equal or lower dose for the monochromatic measurements.
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Affiliation(s)
- Lisa Heck
- Technical University of Munich, Chair of Biomedical Physics, Munich School of BioEngineering, Department of Physics, Garching, Germany
| | - Elena Eggl
- Technical University of Munich, Chair of Biomedical Physics, Munich School of BioEngineering, Department of Physics, Garching, Germany
| | - Susanne Grandl
- Ludwig Maximilian University of Munich, Institute for Clinical Radiology, Munich, Germany
| | - Martin Dierolf
- Technical University of Munich, Chair of Biomedical Physics, Munich School of BioEngineering, Department of Physics, Garching, Germany
| | - Christoph Jud
- Technical University of Munich, Chair of Biomedical Physics, Munich School of BioEngineering, Department of Physics, Garching, Germany
| | - Benedikt Günther
- Technical University of Munich, Chair of Biomedical Physics, Munich School of BioEngineering, Department of Physics, Garching, Germany
| | - Klaus Achterhold
- Technical University of Munich, Chair of Biomedical Physics, Munich School of BioEngineering, Department of Physics, Garching, Germany
| | - Doris Mayr
- Ludwig Maximilian University of Munich, Institute of Pathology, Munich, Germany
| | - Bernhard Gleich
- Technical University of Munich, Chair of Biomedical Physics, Munich School of BioEngineering, Department of Physics, Garching, Germany
| | - Karin Hellerhoff
- Ludwig Maximilian University of Munich, Institute for Clinical Radiology, Munich, Germany
| | - Franz Pfeiffer
- Technical University of Munich, Chair of Biomedical Physics, Munich School of BioEngineering, Department of Physics, Garching, Germany.,Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Department of Diagnostic and Interventional Radiology, Munich, Germany
| | - Julia Herzen
- Technical University of Munich, Chair of Biomedical Physics, Munich School of BioEngineering, Department of Physics, Garching, Germany
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Ruth V, Kolditz D, Steiding C, Kalender WA. Investigation of spectral performance for single-scan contrast-enhanced breast CT using photon-counting technology: A phantom study. Med Phys 2020; 47:2826-2837. [PMID: 32155660 DOI: 10.1002/mp.14133] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 01/17/2020] [Accepted: 03/03/2020] [Indexed: 12/14/2022] Open
Abstract
PURPOSE Contrast-enhanced imaging of the breast is frequently used in breast MRI and has recently become more common in mammography. The purpose of this study was to make single-scan contrast-enhanced imaging feasible for photon-counting breast CT (pcBCT) and to assess the spectral performance of a pcBCT scanner by evaluating iodine maps and virtual non-contrast (VNC) images. METHODS We optimized the settings of a pcBCT to maximize the signal-to-noise ratio between iodinated contrast agent and breast tissue. Therefore, an electronic energy threshold dividing the x-ray spectrum used into two energy bins was swept from 23.17 keV to 50.65 keV. Validation measurements were performed by placing syringes with contrast agent (2.5 mg/ml to 40 mg/ml) in phantoms with 7.5 cm and 12 cm in diameter. Images were acquired at different tube currents and reconstructed with 300 μm isotropic voxel size. Iodine maps and VNC images were generated using image-based material decomposition. Iodine concentrations and CT values were measured for each syringe and compared to the known concentrations and reference CT values. RESULTS Maximal signal-to-noise ratios were found at a threshold position of 32.59 keV. Accurate iodine quantification (average root mean square error of 0.56 mg/ml) was possible down to a concentration of 2.5 mg/ml for all tube currents investigated. The enhancement has been sufficiently removed in the VNC images, so they can be interpreted as unenhanced CT images. Only minor changes of CT values compared to a conventional CT scan were observed. Noise was increased by the decomposition by a factor of 2.62 and 4.87 (7.5 cm and 12 cm phantoms) but did not compromise the accuracy of the iodine quantification. CONCLUSIONS Accurate iodine quantification and generation of VNC images can be achieved using contrast-enhanced pcBCT from a single CT scan in the absence of temporal or spatial misalignment. Using iodine maps and VNC images, pcBCT has the potential to reduce dose, shorten examination and reading time, and to increase cancer detection rates.
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Affiliation(s)
- Veikko Ruth
- Institute of Medical Physics, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, 91052, Germany.,AB-CT - Advanced Breast-CT GmbH, Erlangen, 91052, Germany
| | - Daniel Kolditz
- AB-CT - Advanced Breast-CT GmbH, Erlangen, 91052, Germany
| | | | - Willi A Kalender
- Institute of Medical Physics, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, 91052, Germany.,AB-CT - Advanced Breast-CT GmbH, Erlangen, 91052, Germany
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Brunetti A, Carnimeo L, Trotta GF, Bevilacqua V. Computer-assisted frameworks for classification of liver, breast and blood neoplasias via neural networks: A survey based on medical images. Neurocomputing 2019. [DOI: 10.1016/j.neucom.2018.06.080] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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11
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Bevilacqua V, Brunetti A, Guerriero A, Trotta GF, Telegrafo M, Moschetta M. A performance comparison between shallow and deeper neural networks supervised classification of tomosynthesis breast lesions images. COGN SYST RES 2019. [DOI: 10.1016/j.cogsys.2018.04.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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12
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X-Ray Phase-Contrast Technology in Breast Imaging: Principles, Options, and Clinical Application. AJR Am J Roentgenol 2018; 211:133-145. [DOI: 10.2214/ajr.17.19179] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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13
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Margolies LR, Salvatore M, Yip R, Tam K, Bertolini A, Henschke C, Yankelevitz D. The chest radiologist's role in invasive breast cancer detection. Clin Imaging 2018; 50:13-19. [DOI: 10.1016/j.clinimag.2017.12.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 10/25/2017] [Accepted: 12/05/2017] [Indexed: 11/12/2022]
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14
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Makeev A, Glick SJ. Low-Dose Contrast-Enhanced Breast CT Using Spectral Shaping Filters: An Experimental Study. IEEE TRANSACTIONS ON MEDICAL IMAGING 2017; 36:2417-2423. [PMID: 28783629 DOI: 10.1109/tmi.2017.2735302] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Iodinated contrast-enhanced X-ray imaging of the breast has been studied with various modalities, including full-field digital mammography (FFDM), digital breast tomosynthesis (DBT), and dedicated breast CT. Contrast imaging with breast CT has a number of advantages over FFDM and DBT, including the lack of breast compression, and generation of fully isotropic 3-D reconstructions. Nonetheless, for breast CT to be considered as a viable tool for routine clinical use, it would be desirable to reduce radiation dose. One approach for dose reduction in breast CT is spectral shaping using X-ray filters. In this paper, two high atomic number filter materials are studied, namely, gadolinium (Gd) and erbium (Er), and compared with Al and Cu filters currently used in breast CT systems. Task-based performance is assessed by imaging a cylindrical poly(methyl methacrylate) phantom with iodine inserts on a benchtop breast CT system that emulates clinical breast CT. To evaluate detectability, a channelized hoteling observer (CHO) is used with sums of Laguerre-Gauss channels. It was observed that spectral shaping using Er and Gd filters substantially increased the dose efficiency (defined as signal-to-noise ratio of the CHO divided by mean glandular dose) as compared with kilovolt peak and filter settings used in commercial and prototype breast CT systems. These experimental phantom study results are encouraging for reducing dose of breast CT, however, further evaluation involving patients is needed.
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15
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Shelton SE, Lindsey BD, Dayton PA, Lee YZ. First-in-Human Study of Acoustic Angiography in the Breast and Peripheral Vasculature. ULTRASOUND IN MEDICINE & BIOLOGY 2017; 43:2939-2946. [PMID: 28982628 PMCID: PMC6267932 DOI: 10.1016/j.ultrasmedbio.2017.08.1881] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 08/20/2017] [Accepted: 08/21/2017] [Indexed: 05/07/2023]
Abstract
Screening with mammography has been found to increase breast cancer survival rates by about 20%. However, the current system in which mammography is used to direct patients toward biopsy or surgical excision also results in relatively high rates of unnecessary biopsy, as 66.8% of biopsies are benign. A non-ionizing radiation imaging approach with increased specificity might reduce the rate of unnecessary biopsies. Quantifying the vascular characteristics within and surrounding lesions represents one potential target for assessing likelihood of malignancy via imaging. In this clinical note, we describe the translation of a contrast-enhanced ultrasound technique, acoustic angiography, to human imaging. We illustrate the feasibility of this technique with initial studies in imaging the hand, wrist and breast using Definity microbubble contrast agent and a mechanically steered prototype dual-frequency transducer in healthy volunteers. Finally, this approach was used to image pre-biopsy Breast Imaging Reporting and Data System (BI-RADS) 4 and 5 lesions <2 cm in depth in 11 patients. Results indicate that sensitivity and spatial resolution are sufficient to image vessels as small as 0.2 mm in diameter at depths of ~15 mm in the human breast. Challenges observed include motion artifacts, as well as limited depth of field and sensitivity, which could be improved by correction algorithms and improved transducer technologies.
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Affiliation(s)
- Sarah E Shelton
- Joint Department of Biomedical Engineering, University of North Carolina-Chapel Hill and North Carolina State University, Raleigh, North Carolina, USA
| | - Brooks D Lindsey
- Joint Department of Biomedical Engineering, University of North Carolina-Chapel Hill and North Carolina State University, Raleigh, North Carolina, USA
| | - Paul A Dayton
- Joint Department of Biomedical Engineering, University of North Carolina-Chapel Hill and North Carolina State University, Raleigh, North Carolina, USA; Biomedical Research Imaging Center, University of North Carolina-Chapel Hill, Chapel Hill, North Carolina, USA.
| | - Yueh Z Lee
- Biomedical Research Imaging Center, University of North Carolina-Chapel Hill, Chapel Hill, North Carolina, USA; Department of Radiology, University of North Carolina-Chapel Hill, Chapel Hill, North Carolina, USA
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Baikejiang R, Zhang W, Zhu D, Hernandez AM, Shakeri SA, Wang G, Qi J, Boone JM, Li C. Kernel-based anatomically-aided diffuse optical tomography reconstruction. Biomed Phys Eng Express 2017. [DOI: 10.1088/2057-1976/aa87bb] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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17
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Seifert PJ, Morgan RC, Conover DL, Arieno AL. Initial Experience with a Cone-beam Breast Computed Tomography-guided Biopsy System. J Clin Imaging Sci 2017; 7:1. [PMID: 28217404 PMCID: PMC5288961 DOI: 10.4103/2156-7514.199055] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 11/18/2016] [Indexed: 11/08/2022] Open
Abstract
Objective: To evaluate our initial experience with a cone-beam breast computed tomography (BCT)-guided breast biopsy system for lesion retrieval in phantom studies for use with a cone-beam BCT imaging system. Materials and Methods: Under the Institutional Review Board approval, a phantom biopsy study was performed using a dedicated BCT-guided biopsy system. Fifteen biopsies were performed on each of the small, medium, and large anthropomorphic breast phantoms with both BCT and stereotactic guidance for comparison. Each set of the 45 phantoms contained masses and calcification clusters of varying sizes. Data included mass/calcium retrieval rate and dose and length of procedure time for phantom studies. Results: Phantom mass and calcium retrieval rate were 100% for BCT and stereotactic biopsy. BCT dose for small and medium breast phantoms was found to be equivalent to or less than the corresponding stereotactic approach. Stereotactic-guided biopsy dose was 34.2 and 62.5 mGy for small and medium breast phantoms, respectively. BCT-guided biopsy dose was 15.4 and 30.0 mGy for small and medium breast phantoms, respectively. Both computed tomography biopsy and stereotactic biopsy study time ranged from 10 to 20 min. Conclusion: Initial experience with a BCT-guided biopsy system has shown to be comparable to stereotactic biopsy in phantom studies with equivalent or decreased dose.
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Affiliation(s)
| | | | - David L Conover
- Radiation Safety Unit, University of Rochester, Rochester, NY, USA
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Baikejiang R, Zhang W, Li C. Diffuse optical tomography for breast cancer imaging guided by computed tomography: A feasibility study. JOURNAL OF X-RAY SCIENCE AND TECHNOLOGY 2017; 25:341-355. [PMID: 27983569 DOI: 10.3233/xst-16183] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Diffuse optical tomography (DOT) has attracted attentions in the last two decades due to its intrinsic sensitivity in imaging chromophores of tissues such as hemoglobin, water, and lipid. However, DOT has not been clinically accepted yet due to its low spatial resolution caused by strong optical scattering in tissues. Structural guidance provided by an anatomical imaging modality enhances the DOT imaging substantially. Here, we propose a computed tomography (CT) guided multispectral DOT imaging system for breast cancer imaging. To validate its feasibility, we have built a prototype DOT imaging system which consists of a laser at the wavelength of 650 nm and an electron multiplying charge coupled device (EMCCD) camera. We have validated the CT guided DOT reconstruction algorithms with numerical simulations and phantom experiments, in which different imaging setup parameters, such as projection number of measurements and width of measurement patch, have been investigated. Our results indicate that an air-cooling EMCCD camera is good enough for the transmission mode DOT imaging. We have also found that measurements at six angular projections are sufficient for DOT to reconstruct the optical targets with 2 and 4 times absorption contrast when the CT guidance is applied. Finally, we have described our future research plan on integration of a multispectral DOT imaging system into a breast CT scanner.
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Wienbeck S, Lotz J, Fischer U. Review of clinical studies and first clinical experiences with a commercially available cone-beam breast CT in Europe. Clin Imaging 2016; 42:50-59. [PMID: 27875762 DOI: 10.1016/j.clinimag.2016.11.011] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 11/07/2016] [Accepted: 11/15/2016] [Indexed: 11/17/2022]
Abstract
The dedicated cone-beam breast computed tomography (CBBCT) is a new and promising imaging modality which provides isotropic, 3D images of the breast with high spatial and contrast resolution. Non-contrast and contrast-enhanced CBBCT (CE-CBBCT) was superior to mammography for the visualization of breast masses, especially in patients with dense breast tissue. CE-CBBCT accurately detects DCIS and distinguishes it from benign causes of microcalcifications when compared with non-contrast CBBCT and mammography. The purpose of this report is to describe the technology and its possible indications, and to present the first results from recent clinical studies, illustrating these with our own image examples.
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Affiliation(s)
- Susanne Wienbeck
- Institute for Diagnostic and Interventional Radiology, Georg-August-University Goettingen, Robert-Koch-Str. 40, 37075 Goettingen, Germany.
| | - Joachim Lotz
- Institute for Diagnostic and Interventional Radiology, Georg-August-University Goettingen, Robert-Koch-Str. 40, 37075 Goettingen, Germany
| | - Uwe Fischer
- Diagnostic Breast Care Center Goettingen, Bahnhofsallee 1d, 37081, Goettingen, Germany
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20
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Erickson DW, Wells JR, Sturgeon GM, Samei E, Dobbins JT, Segars WP, Lo JY. Population of 224 realistic human subject-based computational breast phantoms. Med Phys 2016; 43:23. [PMID: 26745896 DOI: 10.1118/1.4937597] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
PURPOSE To create a database of highly realistic and anatomically variable 3D virtual breast phantoms based on dedicated breast computed tomography (bCT) data. METHODS A tissue classification and segmentation algorithm was used to create realistic and detailed 3D computational breast phantoms based on 230 + dedicated bCT datasets from normal human subjects. The breast volume was identified using a coarse three-class fuzzy C-means segmentation algorithm which accounted for and removed motion blur at the breast periphery. Noise in the bCT data was reduced through application of a postreconstruction 3D bilateral filter. A 3D adipose nonuniformity (bias field) correction was then applied followed by glandular segmentation using a 3D bias-corrected fuzzy C-means algorithm. Multiple tissue classes were defined including skin, adipose, and several fractional glandular densities. Following segmentation, a skin mask was produced which preserved the interdigitated skin, adipose, and glandular boundaries of the skin interior. Finally, surface modeling was used to produce digital phantoms with methods complementary to the XCAT suite of digital human phantoms. RESULTS After rejecting some datasets due to artifacts, 224 virtual breast phantoms were created which emulate the complex breast parenchyma of actual human subjects. The volume breast density (with skin) ranged from 5.5% to 66.3% with a mean value of 25.3% ± 13.2%. Breast volumes ranged from 25.0 to 2099.6 ml with a mean value of 716.3 ± 386.5 ml. Three breast phantoms were selected for imaging with digital compression (using finite element modeling) and simple ray-tracing, and the results show promise in their potential to produce realistic simulated mammograms. CONCLUSIONS This work provides a new population of 224 breast phantoms based on in vivo bCT data for imaging research. Compared to previous studies based on only a few prototype cases, this dataset provides a rich source of new cases spanning a wide range of breast types, volumes, densities, and parenchymal patterns.
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Affiliation(s)
- David W Erickson
- Carl E. Ravin Advanced Imaging Laboratories, Duke University Medical Center, Durham, North Carolina 27705 and Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705
| | - Jered R Wells
- Clinical Imaging Physics Group and Carl E. Ravin Advanced Imaging Laboratories, Duke University Medical Center, Durham, North Carolina 27705 and Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705
| | - Gregory M Sturgeon
- Carl E. Ravin Advanced Imaging Laboratories, Duke University Medical Center, Durham, North Carolina 27705
| | - Ehsan Samei
- Department of Radiology and Carl E. Ravin Advanced Imaging Laboratories, Duke University Medical Center, Durham, North Carolina 27705 and Departments of Physics, Electrical and Computer Engineering, and Biomedical Engineering, and Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705
| | - James T Dobbins
- Department of Radiology and Carl E. Ravin Advanced Imaging Laboratories, Duke University Medical Center, Durham, North Carolina 27705 and Departments of Physics and Biomedical Engineering and Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705
| | - W Paul Segars
- Department of Radiology and Carl E. Ravin Advanced Imaging Laboratories, Duke University Medical Center, Durham, North Carolina 27705 and Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705
| | - Joseph Y Lo
- Department of Radiology and Carl E. Ravin Advanced Imaging Laboratories, Duke University Medical Center, Durham, North Carolina 27705 and Departments of Electrical and Computer Engineering and Biomedical Engineering and Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705
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Li M, Zhao Y, Zhang P. Attenuator design method for dedicated whole-core CT. OPTICS EXPRESS 2016; 24:22749-22765. [PMID: 27828346 DOI: 10.1364/oe.24.022749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
In whole-core CT imaging, scanned data corresponding to the central portion of a cylindrical core often suffer from photon starvation, because increasing photon flux will cause overflow on some detector units under the restriction of detector dynamic range. Either photon starvation or data overflow will lead to increased noise or severe artifacts in the reconstructed CT image. In addition, cupping shaped beam hardening artifacts also appear in the whole-core CT image. In this paper, we present a method to design an attenuator for cone beam whole-core CT, which not only reduces the dynamic range requirement for high SNR data scanning, but also corrects beam hardening artifacts. Both simulation and real data are employed to verify our design method.
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22
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Chaudhari AJ, Ferrero A, Godinez F, Yang K, Shelton DK, Hunter JC, Naguwa SM, Boone JM, Raychaudhuri SP, Badawi RD. High-resolution (18)F-FDG PET/CT for assessing disease activity in rheumatoid and psoriatic arthritis: findings of a prospective pilot study. Br J Radiol 2016; 89:20160138. [PMID: 27109738 PMCID: PMC5257326 DOI: 10.1259/bjr.20160138] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 04/05/2016] [Accepted: 04/20/2016] [Indexed: 12/29/2022] Open
Abstract
OBJECTIVE Rheumatoid arthritis (RA) and psoriatic arthritis (PsA) commonly affect the small joints of the wrist and hand. We evaluated the performance of a new, high-resolution extremity positron emission tomography (PET)/CT scanner for characterizing and quantifying pathologies associated with the two arthritides in the wrist and hand joints. METHODS Patients with RA or PsA underwent fluorine-18 fludeoxyglucose ((18)F-FDG) PET/CT wrist and hand imaging, respectively, on the high-resolution scanner. Calibrated CT images and co-registered PET images were reconstructed. PET/CT was derived for the radiocarpal and pisiform-triquetral compartments, joints with erosive changes, sites of synovitis or tenosynovitis and the nail bed and were correlated with clinical and MRI findings. RESULTS Significantly elevated (18)F-FDG uptake was measured for the radiocarpal and pisiform-triquetral compartments and at sites of bone erosion, synovitis, pannus and oedema, compared with unaffected joints (p < 0.05) in patients with RA, consistent with their clinical findings. In patients with PsA, significantly elevated (18)F-FDG uptake was measured for joints with synovitis compared with unaffected joints (p < 0.05), with patterns of (18)F-FDG uptake along the tendons, at the enthesis and in the nail bed, consistent with tenosynovitis, enthesitis and nail dystrophy, respectively. CONCLUSION High-resolution (18)F-FDG PET/CT imaging of the wrist and hand is feasible in an RA or PsA patient cohort and is capable of providing quantifiable measures of disease activity (synovitis, enthesitis, oedema and bone destruction). ADVANCES IN KNOWLEDGE High-resolution PET/CT imaging shows promise as a tool for understanding the pathogenesis of the arthritic process and for non-invasive, objective assessment of RA or PsA severity and therapy selection.
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Affiliation(s)
- Abhijit J Chaudhari
- Department of Radiology, University of California Davis, Sacramento, CA, USA
| | - Andrea Ferrero
- Department of Radiology, University of California Davis, Sacramento, CA, USA
- Department of Radiology, Mayo Clinic, Rochester, MN, USA
| | - Felipe Godinez
- Department of Radiology, University of California Davis, Sacramento, CA, USA
| | - Kai Yang
- Department of Radiology, University of California Davis, Sacramento, CA, USA
- Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
| | - David K Shelton
- Department of Radiology, University of California Davis, Sacramento, CA, USA
| | - John C Hunter
- Department of Radiology, University of California Davis, Sacramento, CA, USA
| | - Stanley M Naguwa
- Department of Internal Medicine, University of California Davis, Sacramento, CA, USA
| | - John M Boone
- Department of Radiology, University of California Davis, Sacramento, CA, USA
| | - Siba P Raychaudhuri
- Department of Internal Medicine, University of California Davis, Sacramento, CA, USA
- Sacramento Veterans Affairs Medical Center, Rancho Cordova, CA, USA
| | - Ramsey D Badawi
- Department of Radiology, University of California Davis, Sacramento, CA, USA
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Shah JP, Mann SD, McKinley RL, Tornai MP. Three dimensional dose distribution comparison of simple and complex acquisition trajectories in dedicated breast CT. Med Phys 2016; 42:4497-510. [PMID: 26233179 DOI: 10.1118/1.4923169] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
PURPOSE A novel breast CT system capable of arbitrary 3D trajectories has been developed to address cone beam sampling insufficiency as well as to image further into the patient's chest wall. The purpose of this study was to characterize any trajectory-related differences in 3D x-ray dose distribution in a pendant target when imaged with different orbits. METHODS Two acquisition trajectories were evaluated: circular azimuthal (no-tilt) and sinusoidal (saddle) orbit with ±15° tilts around a pendant breast, using Monte Carlo simulations as well as physical measurements. Simulations were performed with tungsten (W) filtration of a W-anode source; the simulated source flux was normalized to the measured exposure of a W-anode source. A water-filled cylindrical phantom was divided into 1 cm(3) voxels, and the cumulative energy deposited was tracked in each voxel. Energy deposited per voxel was converted to dose, yielding the 3D distributed dose volumes. Additionally, three cylindrical phantoms of different diameters (10, 12.5, and 15 cm) and an anthropomorphic breast phantom, initially filled with water (mimicking pure fibroglandular tissue) and then with a 75% methanol-25% water mixture (mimicking 50-50 fibroglandular-adipose tissues), were used to simulate the pendant breast geometry and scanned on the physical system. Ionization chamber calibrated radiochromic film was used to determine the dose delivered in a 2D plane through the center of the volume for a fully 3D CT scan using the different orbits. RESULTS Measured experimental results for the same exposure indicated that the mean dose measured throughout the central slice for different diameters ranged from 3.93 to 5.28 mGy, with the lowest average dose measured on the largest cylinder with water mimicking a homogeneously fibroglandular breast. These results align well with the cylinder phantom Monte Carlo studies which also showed a marginal difference in dose delivered by a saddle trajectory in the central slice. Regardless of phantom material or filled fluid density, dose delivered by the saddle scan was negligibly different than the simple circular, no-tilt scans. The average dose measured in the breast phantom was marginally higher for saddle than the circular no tilt scan at 3.82 and 3.87 mGy, respectively. CONCLUSIONS Not only does nontraditional 3D-trajectory CT scanning yield more complete sampling of the breast volume but also has comparable dose deposition throughout the breast and anterior chest volume, as verified by Monte Carlo simulation and physical measurements.
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Affiliation(s)
- Jainil P Shah
- Department of Biomedical Engineering, Duke University, Durham, North Carolina 27705 and Multi Modality Imaging Lab, Duke University Medical Center, Durham, North Carolina 27710
| | - Steve D Mann
- Medical Physics Graduate Program, Duke University Medical Center, Durham, North Carolina 27705 and Multi Modality Imaging Lab, Duke University Medical Center, Durham, North Carolina 27710
| | | | - Martin P Tornai
- Department of Biomedical Engineering, Duke University, Durham, North Carolina 27705; Medical Physics Graduate Program, Duke University Medical Center, Durham, North Carolina 27705; and Multi Modality Imaging Lab, Duke University Medical Center, Durham, North Carolina 27710
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Differentiation of Malignant and Benign Incidental Breast Lesions Detected by Chest Multidetector-Row Computed Tomography: Added Value of Quantitative Enhancement Analysis. PLoS One 2016; 11:e0154569. [PMID: 27128524 PMCID: PMC4851406 DOI: 10.1371/journal.pone.0154569] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 04/15/2016] [Indexed: 11/19/2022] Open
Abstract
To retrospectively determine the association between breast lesion morphology and malignancy and to determine the optimal value of lesion enhancement (HU, Hounsfield units) to improve the diagnostic accuracy of breast cancer in patients with incidental breast lesions (IBLs). A total of 97 patients with 102 IBLs detected from July 2009 to December 2012 were enrolled in this study. Two radiologists analyzed CT images for the presence of malignancy based on the morphology of the lesions alone and in combination with an enhancement value (HU) analysis. There were 36 malignant and 66 benign IBLs. When the morphology and enhancement values were combined, the sensitivity, specificity, and accuracy were 92%, 97%, and 95%, respectively, for reader 1 and 89%, 94%, and 92%, respectively, for reader 2. The addition of HU values led to correct changes in the diagnosis; specifically, the accuracy of the diagnosis of reader 1 and reader 2 improved by 6.9% and 11.8%, respectively. The addition of the enhancement value (HU) to the CT morphology improved the diagnostic accuracy in the differentiation of malignant from benign IBLs by using the region of interest (ROI) to measure the HU within the most suspicious part of the lesion.
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25
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Ng KH, Lau S. Vision 20/20: Mammographic breast density and its clinical applications. Med Phys 2015; 42:7059-77. [PMID: 26632060 DOI: 10.1118/1.4935141] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Affiliation(s)
- Kwan-Hoong Ng
- Department of Biomedical Imaging and University of Malaya Research Imaging Centre, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Susie Lau
- Department of Biomedical Imaging and University of Malaya Research Imaging Centre, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
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Ruile G, Djanatliev A, Kriza C, Meier F, Leb I, Kalender WA, Kolominsky-Rabas PL. Screening for breast cancer with Breast-CT in a ProHTA simulation. J Comp Eff Res 2015; 4:553-67. [DOI: 10.2217/cer.15.42] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Aims: The potential of dedicated Breast-CT is evaluated by simulating its impact onto the performance of the German breast cancer screening program. Attendance rates, cancer detection and economic implications are quantified. Methods: Based on a prospective health technology assessment approach, we simulated screening in different scenarios. Results: In the simulation, attendance rates increase from 54 to up to 72% due to reduced pain. Breast cancers will be detected earlier while nodal positives and distant recurrences decrease. Assuming no additional cost, cost savings of up to €55 million in one screening period are computed. Conclusion: The simulation indicates that earlier cancer detection, fewer unnecessary biopsies and less pain are potential benefits of Breast-CT resulting in cost savings and higher attendance.
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Affiliation(s)
- Georg Ruile
- Institute of Medical Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Bavaria, Germany
- National Leading-Edge Cluster Medical Technologies ‘Medical Valley EMN’, Erlangen, Bavaria, Germany
| | - Anatoli Djanatliev
- Chair for Computer Networks & Communication Systems (Computer Science 7), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Bavaria, Germany
| | - Christine Kriza
- National Leading-Edge Cluster Medical Technologies ‘Medical Valley EMN’, Erlangen, Bavaria, Germany
- Interdisciplinary Centre for Health Technology Assessment (HTA) & Public Health (IZPH), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Bavaria, Germany
| | - Florian Meier
- Department of Health Management, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Nürnberg, Bavaria, Germany
| | - Ines Leb
- Chair of Medical Informatics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Bavaria, Germany
| | - Willi A Kalender
- Institute of Medical Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Bavaria, Germany
- National Leading-Edge Cluster Medical Technologies ‘Medical Valley EMN’, Erlangen, Bavaria, Germany
| | - Peter L Kolominsky-Rabas
- National Leading-Edge Cluster Medical Technologies ‘Medical Valley EMN’, Erlangen, Bavaria, Germany
- Interdisciplinary Centre for Health Technology Assessment (HTA) & Public Health (IZPH), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Bavaria, Germany
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Muralidhar GS, Bovik AC, Markey MK. Disparity Estimation on Stereo Mammograms. IEEE TRANSACTIONS ON IMAGE PROCESSING : A PUBLICATION OF THE IEEE SIGNAL PROCESSING SOCIETY 2015; 24:2851-2863. [PMID: 25974940 DOI: 10.1109/tip.2015.2432714] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We consider the problem of depth estimation on digital stereo mammograms. Being able to elucidate 3D information from stereo mammograms is an important precursor to conducting 3D digital analysis of data from this promising new modality. The problem is generally much harder than the classic stereo matching problem on visible light images of the natural world, since nearly all of the 3D structural information of interest exists as complex network of multilayered, heavily occluded curvilinear structures. Toward addressing this difficult problem, we formulate a new stereo model that minimizes a global energy functional to densely estimate disparity on stereo mammogram images, by introducing a new singularity index as a constraint to obtain better estimates of disparity along critical curvilinear structures. Curvilinear structures, such as vasculature and spicules, are particularly salient structures in the breast, and being able to accurately position them in 3D is a valuable goal. Experiments on synthetic images with known ground truth and on real stereo mammograms highlight the advantages of the proposed stereo model over the canonical stereo model.
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Bazalova-Carter M. The potential of L-shell X-ray fluorescence CT (XFCT) for molecular imaging. Br J Radiol 2015. [PMID: 26204972 DOI: 10.1259/bjr.20140308] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
X-ray fluorescence CT (XFCT), a novel modality proposed for high-sensitivity high-resolution molecular imaging of probes labelled with a high atomic-number element, has been performed with high-energy K-shell X-rays. XFCT performed with low-energy L-shell X-rays could, in principle, result in an increase of XFCT imaging sensitivity; however, the significant L-shell X-ray attenuation limits its use for imaging of small objects. This commentary discusses the advantages and drawbacks of L-shell XFCT imaging.
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Affiliation(s)
- Magdalena Bazalova-Carter
- 1 Department of Radiation Oncology, Stanford University, Stanford, CA, USA.,2 Department of Physics and Astronomy, University of Victoria, Victoria, BC, Canada
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Evaluation of the role of dynamic 64-MDCT in the characterization and work up of breast cancer. THE EGYPTIAN JOURNAL OF RADIOLOGY AND NUCLEAR MEDICINE 2015. [DOI: 10.1016/j.ejrnm.2015.02.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Kuttig JD, Steiding C, Kolditz D, Hupfer M, Karolczak M, Kalender WA. Comparative investigation of the detective quantum efficiency of direct and indirect conversion detector technologies in dedicated breast CT. Phys Med 2015; 31:406-13. [DOI: 10.1016/j.ejmp.2015.03.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Revised: 03/13/2015] [Accepted: 03/16/2015] [Indexed: 10/23/2022] Open
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Sarno A, Mettivier G, Russo P. Dedicated breast computed tomography: Basic aspects. Med Phys 2015; 42:2786-804. [DOI: 10.1118/1.4919441] [Citation(s) in RCA: 88] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
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Lück F, Kolditz D, Hupfer M, Steiding C, Kalender WA. Experimental validation of a single shaped filter approach for CT using variable source-to-filter distance for examination of arbitrary object diameters. Phys Med Biol 2014; 59:5691-706. [PMID: 25198916 DOI: 10.1088/0031-9155/59/19/5691] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The purpose of this study was to validate the use of a single shaped filter (SF) for computed tomography (CT) using variable source-to-filter distance (SFD) for the examination of different object diameters.A SF was designed by performing simulations with the purpose of achieving noise homogeneity in the reconstructed volume and dose reduction for arbitrary phantom diameters. This was accomplished by using a filter design method thats target is to achieve a homogeneous detector noise, but also uses a correction factor for the filtered back projection process. According to simulation results, a single SF designed for one of the largest phantom diameters meets the requirements for all diameters when SFD can be adjusted. To validate these results, a SF made of aluminium alloy was manufactured. Measurements were performed on a CT scanner with polymethyl methacrylate (PMMA) phantoms of diameters from 40-100 mm. The filter was positioned at SFDs ranging from 97-168 mm depending on the phantom diameter. Image quality was evaluated for the reconstructed volume by assessing CT value accuracy, noise homogeneity, contrast-to-noise ratio weighted by dose (CNRD) and spatial resolution. Furthermore, scatter distribution was determined with the use of a beam-stop phantom. Dose was measured for a PMMA phantom with a diameter of 100 mm using a calibrated ionization chamber.The application of a single SF at variable SFD led to improved noise uniformity and dose reduction: noise homogeneity was improved from 15% down to about 0%, and dose was reduced by about 37%. Furthermore, scatter dropped by about 32%, which led to reduced cupping artifacts and improved CT value accuracy. Spatial resolution and CNRD was not affected by the SF.By means of a single SF with variable SFD designed for CT, significant dose reduction can be achieved and image quality can be improved by reducing noise inhomogeneity as well as scatter-induced artifacts.
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Affiliation(s)
- Ferdinand Lück
- Institute of Medical Physics, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany. CT Imaging GmbH, Erlangen, Germany
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Bioelectrical Impedance Methods for Noninvasive Health Monitoring: A Review. J Med Eng 2014; 2014:381251. [PMID: 27006932 PMCID: PMC4782691 DOI: 10.1155/2014/381251] [Citation(s) in RCA: 120] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2013] [Revised: 11/26/2013] [Accepted: 11/26/2013] [Indexed: 01/10/2023] Open
Abstract
Under the alternating electrical excitation, biological tissues produce a complex electrical impedance which depends on tissue composition, structures, health status, and applied signal frequency, and hence the bioelectrical impedance methods can be utilized for noninvasive tissue characterization. As the impedance responses of these tissue parameters vary with frequencies of the applied signal, the impedance analysis conducted over a wide frequency band provides more information about the tissue interiors which help us to better understand the biological tissues anatomy, physiology, and pathology. Over past few decades, a number of impedance based noninvasive tissue characterization techniques such as bioelectrical impedance analysis (BIA), electrical impedance spectroscopy (EIS), electrical impedance plethysmography (IPG), impedance cardiography (ICG), and electrical impedance tomography (EIT) have been proposed and a lot of research works have been conducted on these methods for noninvasive tissue characterization and disease diagnosis. In this paper BIA, EIS, IPG, ICG, and EIT techniques and their applications in different fields have been reviewed and technical perspective of these impedance methods has been presented. The working principles, applications, merits, and demerits of these methods has been discussed in detail along with their other technical issues followed by present status and future trends.
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Ding H, Ducote JL, Molloi S. Measurement of breast tissue composition with dual energy cone-beam computed tomography: a postmortem study. Med Phys 2014; 40:061902. [PMID: 23718593 DOI: 10.1118/1.4802734] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE To investigate the feasibility of a three-material compositional measurement of water, lipid, and protein content of breast tissue with dual kVp cone-beam computed tomography (CT) for diagnostic purposes. METHODS Simulations were performed on a flat panel-based computed tomography system with a dual kVp technique in order to guide the selection of experimental acquisition parameters. The expected errors induced by using the proposed calibration materials were also estimated by simulation. Twenty pairs of postmortem breast samples were imaged with a flat-panel based dual kVp cone-beam CT system, followed by image-based material decomposition using calibration data obtained from a three-material phantom consisting of water, vegetable oil, and polyoxymethylene plastic. The tissue samples were then chemically decomposed into their respective water, lipid, and protein contents after imaging to allow direct comparison with data from dual energy decomposition. RESULTS Guided by results from simulation, the beam energies for the dual kVp cone-beam CT system were selected to be 50 and 120 kVp with the mean glandular dose divided equally between each exposure. The simulation also suggested that the use of polyoxymethylene as the calibration material for the measurement of pure protein may introduce an error of -11.0%. However, the tissue decomposition experiments, which employed a calibration phantom made out of water, oil, and polyoxymethylene, exhibited strong correlation with data from the chemical analysis. The average root-mean-square percentage error for water, lipid, and protein contents was 3.58% as compared with chemical analysis. CONCLUSIONS The results of this study suggest that the water, lipid, and protein contents can be accurately measured using dual kVp cone-beam CT. The tissue compositional information may improve the sensitivity and specificity for breast cancer diagnosis.
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Affiliation(s)
- Huanjun Ding
- Department of Radiological Sciences, University of California, Irvine, California 92697, USA
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Willekens I, Van de Casteele E, Buls N, Temmermans F, Jansen B, Deklerck R, de Mey J. High-resolution 3D micro-CT imaging of breast microcalcifications: a preliminary analysis. BMC Cancer 2014; 14:9. [PMID: 24393444 PMCID: PMC3893600 DOI: 10.1186/1471-2407-14-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Accepted: 12/18/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Detection of microcalcifications on mammograms indicates the presence of breast lesion, and the shapes of the microcalcifications as seen by conventional mammography correlates with the probability of malignancy. This preliminary study evaluated the 3D shape of breast microcalcifications using micro-computed tomography (micro-CT) and compared the findings with those obtained using anatomopathological analysis. METHODS The study analyzed breast biopsy samples from 11 women with findings of suspicious microcalcifications on routine mammograms. The samples were imaged using a micro-CT (SkyScan 1076) at a resolution of 35 μm. Images were reconstructed using filtered back-projection and analyzed in 3D using surface rendering. The samples were subsequently analyzed by the pathology service. Reconstructed 3D images were compared with the corresponding histological slices. RESULTS Anatomopathological analysis showed that 5 of 11 patients had ductal breast carcinoma in situ. One patient was diagnosed with invasive ductal carcinoma.Individual object analysis was performed on 597 microcalcifications. Malignant microcalcifications tended to be thinner and to have a smaller volume and surface area, while their surface area-to-volume ratio was greater than that of benign microcalcifications. The structure model index values were the same for malignant and benign microcalcifications. CONCLUSIONS This is the first study to use micro-CT for quantitative 3D analysis of microcalcifications. This high-resolution imaging technique will be valuable for gaining a greater understanding of the morphologic characteristics of malignant and benign microcalcifications. The presence of many small microcalcifications can be an indication of malignancy. For the larger microcalcifications, 3D parameters confirmed the more irregular shape of malignant microcalcifications.
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Affiliation(s)
- Inneke Willekens
- In vivo Cellular and Molecular Imaging Lab (ICMI), Vrije Universiteit Brussel (VUB), Brussels, Belgium.
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Silkwood JD, Matthews KL, Shikhaliev PM. Photon counting spectral breast CT: effect of adaptive filtration on CT numbers, noise, and contrast to noise ratio. Med Phys 2013; 40:051905. [PMID: 23635275 DOI: 10.1118/1.4800504] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE Photon counting spectral (PCS) computed tomography (CT) shows promise for breast imaging. An issue with current photon-counting detectors is low count rate capabilities, artifacts resulting from nonuniform count rate across the field of view, and suboptimal spectral information. These issues are addressed in part by using tissue-equivalent adaptive filtration of the x-ray beam. The purpose of the study was to investigate the effect of adaptive filtration on different aspects of PCS breast CT. METHODS The theoretical formulation for the filter shape was derived for different filter materials and evaluated by simulation and an experimental prototype of the filter was fabricated from a tissue-like material (acrylic). The PCS CT images of a glandular breast phantom with adipose and iodine contrast elements were simulated at 40, 60, 90, and 120 kVp tube voltages, with and without adaptive filter. The CT numbers, CT noise, and contrast-to-noise ratio (CNR) were compared for spectral CT images acquired with and without adaptive filters. Similar comparison was made for material-decomposed PCS CT images. RESULTS The adaptive filter improved the uniformity of CT numbers, CT noise, and CNR in both ordinary and material decomposed PCS CT images. At the same tube output the average CT noise with adaptive filter, although uniform, was higher than the average noise without adaptive filter due to x-ray absorption by the filter. Increasing tube output, so that average skin exposure with the adaptive filter was same as without filter, made the noise with adaptive filter comparable to or lower than that without adaptive filter. Similar effects were observed when energy weighting was applied, and when material decompositions were performed using energy selective CT data. CONCLUSIONS An adaptive filter decreases count rate requirements to the photon counting detectors which enables PCS breast CT based on commercially available detector technologies. Adaptive filter also improves image quality in PCS breast CT by decreasing beam hardening artifacts and by eliminating spatial nonuniformities of CT numbers, noise, and CNR.
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Affiliation(s)
- Justin D Silkwood
- Imaging Physics Laboratory, Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana 70817, USA
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Nuevas tecnologías en mamografía y su impacto en los valores de dosis. RADIOLOGIA 2013; 55 Suppl 2:25-34. [DOI: 10.1016/j.rx.2013.09.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Revised: 09/11/2013] [Accepted: 09/25/2013] [Indexed: 11/18/2022]
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Hsu CML, Palmeri ML, Segars WP, Veress AI, Dobbins JT. Generation of a suite of 3D computer-generated breast phantoms from a limited set of human subject data. Med Phys 2013; 40:043703. [PMID: 23556929 DOI: 10.1118/1.4794924] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
PURPOSE The authors previously reported on a three-dimensional computer-generated breast phantom, based on empirical human image data, including a realistic finite-element based compression model that was capable of simulating multimodality imaging data. The computerized breast phantoms are a hybrid of two phantom generation techniques, combining empirical breast CT (bCT) data with flexible computer graphics techniques. However, to date, these phantoms have been based on single human subjects. In this paper, the authors report on a new method to generate multiple phantoms, simulating additional subjects from the limited set of original dedicated breast CT data. The authors developed an image morphing technique to construct new phantoms by gradually transitioning between two human subject datasets, with the potential to generate hundreds of additional pseudoindependent phantoms from the limited bCT cases. The authors conducted a preliminary subjective assessment with a limited number of observers (n = 4) to illustrate how realistic the simulated images generated with the pseudoindependent phantoms appeared. METHODS Several mesh-based geometric transformations were developed to generate distorted breast datasets from the original human subject data. Segmented bCT data from two different human subjects were used as the "base" and "target" for morphing. Several combinations of transformations were applied to morph between the "base' and "target" datasets such as changing the breast shape, rotating the glandular data, and changing the distribution of the glandular tissue. Following the morphing, regions of skin and fat were assigned to the morphed dataset in order to appropriately assign mechanical properties during the compression simulation. The resulting morphed breast was compressed using a finite element algorithm and simulated mammograms were generated using techniques described previously. Sixty-two simulated mammograms, generated from morphing three human subject datasets, were used in a preliminary observer evaluation where four board certified breast radiologists with varying amounts of experience ranked the level of realism (from 1 = "fake" to 10 = "real") of the simulated images. RESULTS The morphing technique was able to successfully generate new and unique morphed datasets from the original human subject data. The radiologists evaluated the realism of simulated mammograms generated from the morphed and unmorphed human subject datasets and scored the realism with an average ranking of 5.87 ± 1.99, confirming that overall the phantom image datasets appeared more "real" than "fake." Moreover, there was not a significant difference (p > 0.1) between the realism of the unmorphed datasets (6.0 ± 1.95) compared to the morphed datasets (5.86 ± 1.99). Three of the four observers had overall average rankings of 6.89 ± 0.89, 6.9 ± 1.24, 6.76 ± 1.22, whereas the fourth observer ranked them noticeably lower at 2.94 ± 0.7. CONCLUSIONS This work presents a technique that can be used to generate a suite of realistic computerized breast phantoms from a limited number of human subjects. This suite of flexible breast phantoms can be used for multimodality imaging research to provide a known truth while concurrently producing realistic simulated imaging data.
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Affiliation(s)
- Christina M L Hsu
- Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708, USA.
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Mun HS, Kim HH, Shin HJ, Cha JH, Ruppel PL, Oh HY, Chae EY. Assessment of extent of breast cancer: comparison between digital breast tomosynthesis and full-field digital mammography. Clin Radiol 2013; 68:1254-9. [PMID: 23969151 DOI: 10.1016/j.crad.2013.07.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Revised: 06/10/2013] [Accepted: 07/09/2013] [Indexed: 10/26/2022]
Abstract
AIM To compare the accuracy of digital breast tomosynthesis (DBT) and full-field digital mammography (FFDM) in preoperative assessment of local extent of breast cancer. MATERIALS AND METHODS Lesion sizes of breast cancers on DBT and FFDM images were independently evaluated by breast radiologists. Each lesion was flagged as either mis-sized or not depending on whether the assessment of size at imaging was within 1 cm of the lesion size at surgery. Additional analyses were made by mammographic parenchymal density and by lesion size, using 2 cm as the boundary to separate the two subgroups. Statistical comparisons were performed using a repeated measures linear model on the percent mis-sized. P-values < 0.05 were considered statistically significant. RESULTS The dataset included 173 malignant breast lesions (mean size 23.8 mm, 43% of lesions were ≤2 cm in size) in 169 patients, two-thirds of which had heterogeneously or extremely dense breasts. Overall, the percentage of lesions mis-sized at DBT was significantly lower than at FFDM (19% versus 29%, p = 0.003). There was significantly less mis-sizing at DBT in both heterogeneously dense breasts (11.1% difference between DBT and FFDM, p = 0.016) and extremely dense breasts (15.8% difference, p = 0.024). DBT also had significantly less mis-sizing than FFDM in the subgroup of lesions that were ≤2 cm in size (14.7% difference, p = 0.005). CONCLUSION DBT was significantly superior to FFDM for the evaluation of lesion size overall, and specifically for small lesions and for lesions in dense breasts. The superiority of DBT versus FFDM increased with parenchymal density.
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Affiliation(s)
- H S Mun
- Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, South Korea; Severance Check-up, Severance Hospital, Yonsei University College of Medicine, Seoul, South Korea
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Lück F, Kolditz D, Hupfer M, Kalender WA. Effect of shaped filter design on dose and image quality in breast CT. Phys Med Biol 2013; 58:4205-23. [PMID: 23715466 DOI: 10.1088/0031-9155/58/12/4205] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The purpose of this study was to investigate the effect of shaped filters specifically designed for dedicated breast computed tomography (CT) scanners on dose and image quality. Optimization of filter shape and material in fan direction was performed using two different design methods, one aiming at homogeneous noise distributions in the CT images and the other aiming at a uniform dose distribution in the breast. The optimal filter thickness as a function of fan angle was determined iteratively to fulfil the above mentioned criteria for each breast diameter. Different filter materials (aluminium, copper, carbon, polytetrafluoroethylene) and breast phantoms with diameters between 80-180 mm were investigated. Noise uniformity in the reconstructed images, obtained from CT simulations based on ray-tracing methods, and dose in the breast, calculated with a Monte Carlo software tool, were used as figure of merit. Furthermore, CT-value homogeneity, the distribution of noise in cone direction, spatial resolution from centre to periphery and the contrast-to-noise ratio weighted by dose (CNRD) were evaluated. In addition, the decrease of scatter due to shaped filters was investigated. Since only few or one filter are practical in clinical CT systems, the effects of one shaped filter for different breast diameters were also investigated. In this case the filter, designed for the largest breast diameter, was simulated at variable source-to-filter distances depending on breast diameter. With the filter design method aiming at uniform noise distribution best results were obtained for aluminium as the filter material. Noise uniformity improved from 20} down to 5} and dose was reduced by about 30-40} for all breast diameters. No decrease of noise uniformity in cone direction, CT-value homogeneity, spatial resolution and the CNRD was detected with the shaped filter. However, a small improvement of CNRD was observed. Furthermore, a scatter reduction of about 20-30} and a more homogeneous scatter distribution were reached which led to reduced cupping artefacts. The simulations with one shaped filter at variable source-to-filter distance resulted in nearly homogeneous noise distributions and comparable dose reduction for all breast diameters. In conclusion, by means of shaped filters designed for breast CT, significant dose reduction can be achieved at unimpaired image quality. One shaped filter designed for the largest breast diameter used with variable source-to-filter distance appears to be the best solution for breast CT.
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Affiliation(s)
- Ferdinand Lück
- Institute of Medical Physics, Friedrich-Alexander-University Erlangen-Nürnberg, 91052 Erlangen, Germany.
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Chen L, Abbey CK, Nosratieh A, Lindfors KK, Boone JM. Anatomical complexity in breast parenchyma and its implications for optimal breast imaging strategies. Med Phys 2013; 39:1435-41. [PMID: 22380376 DOI: 10.1118/1.3685462] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
PURPOSE The purpose of this investigation was to assess the anatomical noise in breast images using a mathematically derived parameter β as a surrogate for detection performance, across the same patient cohort but in different imaging modalities including mammography, tomosynthesis, and breast CT. METHODS Women who were scheduled for breast biopsy were approached for participation in this IRB and HIPPA-compliant investigation. A total of 23 women had all views of each modality and represent the cohort studied in this investigation. Image data sets across all modalities were analyzed using 1000 regions of interest per image data set, and the anatomical noise power spectrum, NPS(a)(f), was computed and averaged for each breast image data set. After windowing the total noise power spectrum NPS(t)(f) to a specific frequency range corresponding to anatomical noise, the power-law slope (β) of the NPS(a)(f) was computed where NPS(a)(f) = α f(-) (β). RESULTS The value of β was determined for breast CT data sets, and they were 1.75 (0.424), 1.83 (0.352), and 1.79 (0.397), for the coronal, sagittal, and axial views, respectively. For tomosynthesis, β was 3.06 (0.361) and 3.10 (0.315) for the craniocaudal (CC) and medial lateral oblique (MLO) views, respectively. For mammography, these values were 3.17 (0.226) and 3.30 (0.236), for the CC and MLO views, respectively. The values of β for breast CT were significantly different than those for tomosynthesis and mammography (p < 0.001, all 12 comparisons). CONCLUSIONS Based on the parameter β which is thought to describe anatomical noise in breast images, breast CT was shown to have a statistically significant lower β than mammography or tomosynthesis. It has been suggested in the literature that a lower β may correspond to increased cancer detection performance; however, this has yet to be demonstrated unequivocally.
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Affiliation(s)
- Lin Chen
- Biomedical Engineering Graduate Group, University of California, Sacramento, CA 95817, USA
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Grandl S, Willner M, Herzen J, Mayr D, Auweter SD, Hipp A, Pfeiffer F, Reiser M, Hellerhoff K. Evaluation of phase-contrast CT of breast tissue at conventional X-ray sources - presentation of selected findings. Z Med Phys 2013; 23:212-21. [PMID: 23489931 DOI: 10.1016/j.zemedi.2013.02.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Revised: 02/14/2013] [Accepted: 02/18/2013] [Indexed: 12/20/2022]
Abstract
BACKGROUND Grating-based phase contrast computed tomography (PC-CT) at synchrotron radiation sources has been shown to provide improved visualization of breast tumors. However, broad clinical application of phase-contrast imaging will likely depend on transferring the technology to standard polychromatic X-ray sources. On the basis of selected findings, we demonstrate the potential of grating-based PC-CT using a conventional X-ray source. MATERIALS AND METHODS Grating-based PC-CT of two ex-vivo formalin fixed breast specimens containing lobular carcinoma was conducted using a Talbot Lau interferometer run at a polychromatic X-ray source of 40kVp. Phase-contrast and absorption-based 3D-datasets of both specimens were simultaneously recorded. Radiological images were manually matched with corresponding histological sections. The visualization of selected histological findings in phase contrast was compared to absorption contrast. RESULTS Grating-based PC-CT was able to depict the 3-dimensional structure of dilated ducts and high phase contrast was found as a correlate to thickened fibrous ductal walls. Differences in contrast between fibrous and less fibrous breast tissue were observed in phase- but not in absorption-contrast images. Furthermore, regions of low phase contrast correlated with the extension of compact tumor components. CONCLUSIONS On the basis of selected findings, we show that grating-based PC-CT at a polychromatic X-ray source provides complementary information to conventional absorption contrast; albeit at lower spatial resolution than synchrotron-based imaging.
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Affiliation(s)
- Susanne Grandl
- Department of Clinical Radiology, Ludwig-Maximilians-Universität München, Marchioninistrasse 15, 81377 Munich, Germany.
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Nosratieh A, Yang K, Aminololama-Shakeri S, Boone JM. Comprehensive assessment of the slice sensitivity profiles in breast tomosynthesis and breast CT. Med Phys 2013; 39:7254-61. [PMID: 23231276 DOI: 10.1118/1.4764908] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE This study experimentally evaluated the slice sensitivity profile (SSP) and its relationship between acquisition angle, object size, and cone angle. The sensitivity profile metric was used to characterize a breast tomosynthesis system's resolution in the z-axis. The SSP was also measured on a prototype breast computed tomography (bCT) system. METHODS The SSP was measured using brass disks placed within adipose tissue-equivalent breast phantoms. The digital tomosynthesis system (Selenia Dimensions, Hologic Corporation, Bedford, MA) acquires projection images over a 15° angular range and the bCT scanner acquires projection images over a 360° angular range. Angular ranges between 15° and 360° were studied by using a subset of the projection images acquired on the bCT scanner. The SSP was determined by measuring a background-corrected mean gray scale value as a function of the z-position (axis normal to the plane of the detector). RESULTS The results show that SSP improves when the angular acquisition range is increased and the SSP approaches a delta function for angles greater than 180°. Smaller objects have a narrower SSP and the SSP is not significantly dependent on the cone angle. For a 2.5, 5, 10 mm disk, the full width at half maximum of the SSP was 35, 61, 115 mm, respectively, on the tomosynthesis system (at 15°) and was 0.5 mm for all disk diameters on the bCT scanner (at 360°). CONCLUSIONS The SSP is dependent on object size and angular acquisition range. These dependencies are overcome once the angular acquisition range is increased beyond 180°.
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Affiliation(s)
- Anita Nosratieh
- Department of Radiology, University of California, Davis, CA 95817, USA
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Svahn TM, Chakraborty DP, Ikeda D, Zackrisson S, Do Y, Mattsson S, Andersson I. Breast tomosynthesis and digital mammography: a comparison of diagnostic accuracy. Br J Radiol 2012; 85:e1074-82. [PMID: 22674710 PMCID: PMC3500806 DOI: 10.1259/bjr/53282892] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2011] [Revised: 02/28/2012] [Accepted: 03/14/2012] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE Our aim was to compare the ability of radiologists to detect breast cancers using one-view breast tomosynthesis (BT) and two-view digital mammography (DM) in an enriched population of diseased patients and benign and/or healthy patients. METHODS All participants gave informed consent. The BT and DM examinations were performed with about the same average glandular dose to the breast. The study population comprised patients with subtle signs of malignancy seen on DM and/or ultrasonography. Ground truth was established by pathology, needle biopsy and/or by 1-year follow-up by mammography, which retrospectively resulted in 89 diseased breasts (1 breast per patient) with 95 malignant lesions and 96 healthy or benign breasts. Two experienced radiologists, who were not participants in the study, determined the locations of the malignant lesions. Five radiologists, experienced in mammography, interpreted the cases independently in a free-response study. The data were analysed by the receiver operating characteristic (ROC) and jackknife alternative free-response ROC (JAFROC) methods, regarding both readers and cases as random effects. RESULTS The diagnostic accuracy of BT was significantly better than that of DM (JAFROC: p=0.0031, ROC: p=0.0415). The average sensitivity of BT was higher than that of DM (∼90% vs ∼79%; 95% confidence interval of difference: 0.036, 0.108) while the average false-positive fraction was not significantly different (95% confidence interval of difference: -0.117, 0.010). CONCLUSION The diagnostic accuracy of BT was superior to DM in an enriched population.
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Affiliation(s)
- T M Svahn
- Medical Radiation Physics, Department of Clinical Sciences Malmö, Lund University, Skåne University Hospital, Malmö, Sweden.
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Packard NJ, Abbey CK, Yang K, Boone JM. Effect of slice thickness on detectability in breast CT using a prewhitened matched filter and simulated mass lesions. Med Phys 2012; 39:1818-30. [PMID: 22482604 DOI: 10.1118/1.3692176] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
PURPOSE Dedicated breast CT (bCT) is an emerging technology with the potential to improve the detection of breast cancer in screening and diagnostic capacities. Typically, the 3D volume reconstructed from the scanner is displayed as sectional images. The purpose of this study was to evaluate the effect of section thickness on the detectability of simulated masses using a prewhitened matched filter (PWMF) as a model observer. METHODS A breast CT scanner has been designed and fabricated in the authors' laboratory with more than 200 women imaged in IRB-approved phase I and phase II trials to date. Of these, 151 bilateral data sets were selected on the basis of low artifact content, sufficient breast coverage, and excluding cases with breast implants. BIRADS breast density ratings were available for 144 of these patients. Spherical mass lesions of diameter 1, 2, 3, 5, 11, and 15 mm were mathematically generated and embedded at random locations within the parenchymal region of each bCT volume. Microcalcifications were not simulated in this study. For each viewing plane (sagittal, axial, and coronal) and section thickness (ranging from 0.3 to 44 mm), section images of the breast parenchyma containing the lesion were generated from the reconstructed bCT data sets by averaging voxels over the length of the section. Using signal known exactly (SKE) model observer methodology, receiver operating characteristic (ROC) curve analysis was performed on each generated projected image using a PWMF based model observer. ROC curves were generated for each breast data set, and the area under the ROC curve (AUC) was evaluated as well as the sensitivity at 95% specificity. RESULTS For all lesion sizes, performance rises modestly to a peak before falling off substantially as section thickness increases over the range of the study. We find that the optimal section thickness tracks the size of the lesion to be detected linearly with a small positive offset and slopes ranging from 0.27 to 0.44. No significant differences were observed between left and right breasts. Performance measures are negatively correlated with measures of breast density, with an average correlation coefficient of -0.48 for the BIRADS breast density score and -0.81 for the proportion of glandular tissue in the breast interior. CONCLUSIONS This study shows quantitatively how PWMF detection performance of a known lesion size is influenced by section thickness in dedicated breast CT. While the optimal section thickness is tuned to the size of the lesion being detected, overall performance is more robust for thin section images compared to thicker images.
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Sechopoulos I. X-ray scatter correction method for dedicated breast computed tomography. Med Phys 2012; 39:2896-903. [PMID: 22559662 DOI: 10.1118/1.4711749] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
PURPOSE To improve image quality and accuracy in dedicated breast computed tomography (BCT) by removing the x-ray scatter signal included in the BCT projections. METHODS The previously characterized magnitude and distribution of x-ray scatter in BCT results in both cupping artifacts and reduction of contrast and accuracy in the reconstructions. In this study, an image processing method is proposed that estimates and subtracts the low-frequency x-ray scatter signal included in each BCT projection postacquisition and prereconstruction. The estimation of this signal is performed using simple additional hardware, one additional BCT projection acquisition with negligible radiation dose, and simple image processing software algorithms. The high frequency quantum noise due to the scatter signal is reduced using a noise filter postreconstruction. The dosimetric consequences and validity of the assumptions of this algorithm were determined using Monte Carlo simulations. The feasibility of this method was determined by imaging a breast phantom on a BCT clinical prototype and comparing the corrected reconstructions to the unprocessed reconstructions and to reconstructions obtained from fan-beam acquisitions as a reference standard. One-dimensional profiles of the reconstructions and objective image quality metrics were used to determine the impact of the algorithm. RESULTS The proposed additional acquisition results in negligible additional radiation dose to the imaged breast (∼0.4% of the standard BCT acquisition). The processed phantom reconstruction showed substantially reduced cupping artifacts, increased contrast between adipose and glandular tissue equivalents, higher voxel value accuracy, and no discernible blurring of high frequency features. CONCLUSIONS The proposed scatter correction method for dedicated breast CT is feasible and can result in highly improved image quality. Further optimization and testing, especially with patient images, is necessary to characterize its impact on clinical performance.
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Affiliation(s)
- Ioannis Sechopoulos
- Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA 30322, USA.
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SREE SVINITHA, NG EDDIEYK, ACHARYA U RAJENDRA, TAN WILLIAM. BREAST IMAGING SYSTEMS: A REVIEW AND COMPARATIVE STUDY. J MECH MED BIOL 2012. [DOI: 10.1142/s0219519410003277] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Due to the successful union between computational technologies and basic laws of physics and biological sciences, many biomedical imaging systems now find significant presence in clinical settings, aiding physicians in diagnosing most forms of human illness with more confidence. In the case of breast imaging, apart from the basic diagnosis, these imaging systems also help in locating the abnormal tissues for biopsy, identifying the exact margins of the lesion for good lumpectomy results, staging and restaging the cancer, detecting locations of metastases, and planning and following up treatment protocols. It is well known that early detection of cancer is the only way to increase the survival rate of the patient. Without such imaging systems, it would be hard and almost impossible for the physicians to determine the nature and extent of the disease by merely simple physical examinations and biopsies. This article presents a description of most of these invaluable breast-imaging systems. Moreover, a comparison of these modalities and a review of a few of the developments these devices have come across over the years are also given.
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Affiliation(s)
- S. VINITHA SREE
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
| | - EDDIE Y.-K. NG
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
- Adjunct NUH Scientist, Office of Biomedical Research, National University Hospital of Singapore, Singapore 117597, Singapore
| | - RAJENDRA ACHARYA U
- Department of Electronics and Computer Engineering, Ngee Ann Polytechnic, Singapore 599489, Singapore
| | - WILLIAM TAN
- Department of Electronics and Computer Engineering, Ngee Ann Polytechnic, Singapore 599489, Singapore
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Sztrókay A, Diemoz PC, Schlossbauer T, Brun E, Bamberg F, Mayr D, Reiser MF, Bravin A, Coan P. High-resolution breast tomography at high energy: a feasibility study of phase contrast imaging on a whole breast. Phys Med Biol 2012; 57:2931-42. [PMID: 22516937 DOI: 10.1088/0031-9155/57/10/2931] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Previous studies on phase contrast imaging (PCI) mammography have demonstrated an enhancement of breast morphology and cancerous tissue visualization compared to conventional imaging. We show here the first results of the PCI analyser-based imaging (ABI) in computed tomography (CT) mode on whole and large (>12 cm) tumour-bearing breast tissues. We demonstrate in this work the capability of the technique of working at high x-ray energies and producing high-contrast images of large and complex specimens. One entire breast of an 80-year-old woman with invasive ductal cancer was imaged using ABI-CT with monochromatic 70 keV x-rays and an area detector of 92×92 µm² pixel size. Sagittal slices were reconstructed from the acquired data, and compared to corresponding histological sections. Comparison with conventional absorption-based CT was also performed. Five blinded radiologists quantitatively evaluated the visual aspects of the ABI-CT images with respect to sharpness, soft tissue contrast, tissue boundaries and the discrimination of different structures/tissues. ABI-CT excellently depicted the entire 3D architecture of the breast volume by providing high-resolution and high-contrast images of the normal and cancerous breast tissues. These results are an important step in the evolution of PCI-CT towards its clinical implementation.
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Affiliation(s)
- A Sztrókay
- Institute of Clinical Radiology, Ludwig-Maximilians University, Munich, Germany
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