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Caballo M, Michielsen K, Fedon C, Sechopoulos I. Towards 4D dedicated breast CT perfusion imaging of cancer: computer simulations of the image generation process. Phys Med 2021. [DOI: 10.1016/s1120-1797(22)00108-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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Caballo M, Hernandez A, Lyu S, Teuwen J, Mann R, van Ginneken B, Boone J, Sechopoulos I. Computer-aided diagnosis of masses in breast CT imaging: combined power of handcrafted and deep learning radiomics. Phys Med 2021. [DOI: 10.1016/s1120-1797(22)00024-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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Anton M, Reginatto M, Elster C, Mäder U, Schopphoven S, Sechopoulos I, van Engen R. The regression detectability index RDI for mammography images of breast phantoms with calcification-like objects and anatomical background. Phys Med Biol 2021; 66. [PMID: 34706354 DOI: 10.1088/1361-6560/ac33ea] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 10/27/2021] [Indexed: 11/11/2022]
Abstract
Currently, quality assurance measurements in mammography are performed on unprocessed images. For diagnosis, however, radiologists are provided with processed images. This image processing is optimised for images of human anatomy and therefore does not always perform satisfactorily with technical phantoms. To overcome this problem, it may be possible to use anthropomorphic phantoms reflecting the anatomic structure of the human breast in place of technical phantoms when carrying out task-specific quality assessment using model observers. However, the use of model observers is hampered by the fact that a large number of images needs to be acquired. A recently published novel observer called the regression detectability index (RDI) needs significantly fewer images, but requires the background of the images to be flat. Therefore, to be able to apply the RDI to images of anthropomorphic phantoms, the anatomic background needs to be removed. For this, a procedure in which the anatomical structures are fitted by thin plate spline (TPS) interpolation has been developed. When the object to be detected is small, such as a calcification-like lesion, it is shown that the anatomic background can be removed successfully by subtracting the TPS interpolation, which makes the background-free image accessible to the RDI. We have compared the detectability obtained by the RDI with TPS background subtraction to results of the channelized Hotelling observer (CHO) and human observers. With the RDI, results for the detectabilityd'can be obtained using 75% fewer images compared to the CHO, while the same uncertainty ofd'is achieved. Furthermore, the correlation ofd'(RDI) with the results of human observers is at least as good as that ofd'(CHO) with human observers.
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Affiliation(s)
- M Anton
- Physikalisch-Technische Bundesanstalt Braunschweig and Berlin, Germany
| | - M Reginatto
- Physikalisch-Technische Bundesanstalt Braunschweig and Berlin, Germany
| | - C Elster
- Physikalisch-Technische Bundesanstalt Braunschweig and Berlin, Germany
| | - U Mäder
- Institute of Medical Physics and Radiation Protection, University of Applied Sciences, Giessen, Germany
| | - S Schopphoven
- Reference Centre for Mammography Screening Southwest Germany, Marburg, Germany
| | - I Sechopoulos
- Radboud University Medical Center, Nijmegen, The Netherlands.,LRCB Dutch Expert Centre for Screening, Nijmegen, The Netherlands
| | - R van Engen
- LRCB Dutch Expert Centre for Screening, Nijmegen, The Netherlands
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Sliwicka O, Habets J, Sechopoulos I. Image Quality Evaluation Of Cardiac Dynamic Stress CT Perfusion With A Novel Noise Reducing Filter. J Cardiovasc Comput Tomogr 2021. [DOI: 10.1016/j.jcct.2021.06.222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Sliwicka O, Sechopoulos I, Habets J. Objective evaluation of improved image quality with application of novel noise reduction filter in dynamic myocardial CT perfusion. Eur Heart J Cardiovasc Imaging 2021. [DOI: 10.1093/ehjci/jeaa356.244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: None.
Background
Dynamic myocardial CT perfusion (CTP) is a non-invasive imaging technique able to depict cardiac ischemia. It is expected that the application of a new dynamic perfusion image noise reducing filter, the similarity filter (4DSF) would improve the image quality of CTP, resulting in clear visualization of perfusion deficits and hypo-perfused tissue and allowing for a substantial reduction in the radiation dose in dynamic myocardial CTP.
Purpose
To evaluate image quality before and after the application of a novel noise reducing filter on dynamic myocardial CT perfusion images reconstructed with deep learning-based algorithm.
Methods
The image datasets of patients with stable chest pain at intermediate risk of cardiovascular disease, who underwent stress dynamic CTP scanning as clinically indicated were retrospectively collected. The images were acquired with a 320-slice CT system, reconstructed using a deep learning-based algorithm (8 mm slice thickness) and filtered with the 4DSF. For each case, the signal-to-noise ratio (SNR) and the contrast-to-noise ratio (CNR) in six regions-of-interest (ROIs, 33-38 mm2) were computed, before and after filtering. The signal ROIs were located midventricular, in both four-chamber and short-axis views in the left ventricle blood pool, and the background ROIs in the cardiac septum and lateral wall. Differences in the SNR and CNR values were compared using paired t-tests.
Results
As a part of an ongoing study, twenty five cases were analysed to date. The following results (means for AiCE and AiCE + 4DSF, and corresponding p-values) were obtained in short axis view: septum SNR: 3.46 vs 6.25 (p = 0.007), lateral wall SNR: 3.66 vs 6.52 (p = 0.000), septum CNR: 13.35 vs 23.85 (p = 0.005), lateral wall CNR: 13.16 vs 23.57 (p = 0.010); and in four-chamber view: septum SNR: 3.67 vs 7.44 (p = 0.003), lateral wall SNR: 3.97 vs 7.65 (p = 0.001) and septum CNR: 13.92 vs 29.97 (p = 0.016), lateral wall CNR: 13.63 vs 29.75 (p = 0.018). All results are statistically significant.
Conclusions
We confirmed that the similarity filter decreases noise and therefore improves the objective image quality in both short axis and four chamber views. Therefore, the improved tissue texture depiction and improved visualization of perfusion defects may facilitate detection of ischemia and lead to reduction in radiation dose necessary for dynamic CTP, maintaining image quality.
Abstract Figure. Region-of-interests (ROIs) location
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Affiliation(s)
- O Sliwicka
- Radboud University Medical Center, Nijmegen, Netherlands (The)
| | - I Sechopoulos
- Radboud University Medical Center, Nijmegen, Netherlands (The)
| | - J Habets
- Radboud University Medical Center, Nijmegen, Netherlands (The)
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Arce P, Bolst D, Bordage MC, Brown JMC, Cirrone P, Cortés-Giraldo MA, Cutajar D, Cuttone G, Desorgher L, Dondero P, Dotti A, Faddegon B, Fedon C, Guatelli S, Incerti S, Ivanchenko V, Konstantinov D, Kyriakou I, Latyshev G, Le A, Mancini-Terracciano C, Maire M, Mantero A, Novak M, Omachi C, Pandola L, Perales A, Perrot Y, Petringa G, Quesada JM, Ramos-Méndez J, Romano F, Rosenfeld AB, Sarmiento LG, Sakata D, Sasaki T, Sechopoulos I, Simpson EC, Toshito T, Wright DH. Report on G4-Med, a Geant4 benchmarking system for medical physics applications developed by the Geant4 Medical Simulation Benchmarking Group. Med Phys 2021; 48:19-56. [PMID: 32392626 PMCID: PMC8054528 DOI: 10.1002/mp.14226] [Citation(s) in RCA: 63] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 04/26/2020] [Accepted: 04/30/2020] [Indexed: 11/05/2022] Open
Abstract
BACKGROUND Geant4 is a Monte Carlo code extensively used in medical physics for a wide range of applications, such as dosimetry, micro- and nanodosimetry, imaging, radiation protection, and nuclear medicine. Geant4 is continuously evolving, so it is crucial to have a system that benchmarks this Monte Carlo code for medical physics against reference data and to perform regression testing. AIMS To respond to these needs, we developed G4-Med, a benchmarking and regression testing system of Geant4 for medical physics. MATERIALS AND METHODS G4-Med currently includes 18 tests. They range from the benchmarking of fundamental physics quantities to the testing of Monte Carlo simulation setups typical of medical physics applications. Both electromagnetic and hadronic physics processes and models within the prebuilt Geant4 physics lists are tested. The tests included in G4-Med are executed on the CERN computing infrastructure via the use of the geant-val web application, developed at CERN for Geant4 testing. The physical observables can be compared to reference data for benchmarking and to results of previous Geant4 versions for regression testing purposes. RESULTS This paper describes the tests included in G4-Med and shows the results derived from the benchmarking of Geant4 10.5 against reference data. DISCUSSION Our results indicate that the Geant4 electromagnetic physics constructor G4EmStandardPhysics_option4 gives a good agreement with the reference data for all the tests. The QGSP_BIC_HP physics list provided an overall adequate description of the physics involved in hadron therapy, including proton and carbon ion therapy. New tests should be included in the next stage of the project to extend the benchmarking to other physical quantities and application scenarios of interest for medical physics. CONCLUSION The results presented and discussed in this paper will aid users in tailoring physics lists to their particular application.
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Affiliation(s)
| | - D Bolst
- Centre For Medical Radiation Physics, University of Wollongong, Wollongong, Australia
| | - M-C Bordage
- CRCT (INSERM and Paul Sabatier University), Toulouse, France
| | - J M C Brown
- Department of Radiation Science and Technology, Delft University of Technology, Delft, The Netherlands
| | | | | | - D Cutajar
- Centre For Medical Radiation Physics, University of Wollongong, Wollongong, Australia
| | | | - L Desorgher
- Institute of Radiation Physics (IRA), Lausanne University Hospital, Lausanne, Switzerland
| | | | - A Dotti
- SLAC National Accelerator Laboratory, Stanford, CA, USA
| | - B Faddegon
- University of California, San Francisco, CA, USA
| | - C Fedon
- Radboud University Medical Center, Nijmegen, The Netherlands
| | - S Guatelli
- Centre For Medical Radiation Physics, University of Wollongong, Wollongong, Australia
| | - S Incerti
- Université de Bordeaux, CNRS/IN2P3, UMR5797, Centre d'Études Nucléaires de Bordeaux Gradignan, Gradignan, France
| | - V Ivanchenko
- Tomsk State University, Tomsk, Russian Federation
- CERN, Geneva, Switzerland
| | - D Konstantinov
- NRC "Kurchatov Institute" - IHEP, Protvino, Russian Federation
| | - I Kyriakou
- Medical Physics Laboratory, University of Ioannina, Ioannina, Greece
| | - G Latyshev
- NRC "Kurchatov Institute" - IHEP, Protvino, Russian Federation
| | - A Le
- Centre For Medical Radiation Physics, University of Wollongong, Wollongong, Australia
| | | | | | | | | | - C Omachi
- Nagoya Proton Therapy Center, Nagoya, Japan
| | | | - A Perales
- Medical Physics Department of Clínica Universidad de Navarra, Pamplona, Spain
| | - Y Perrot
- IRSN, Fontenay-aux-Roses, France
| | | | | | | | - F Romano
- INFN Catania Section, Catania, Italy
- Medical Physics Department, National Physical Laboratory, Teddington, UK
| | - A B Rosenfeld
- Centre For Medical Radiation Physics, University of Wollongong, Wollongong, Australia
| | | | - D Sakata
- Centre For Medical Radiation Physics, University of Wollongong, Wollongong, Australia
| | | | - I Sechopoulos
- Radboud University Medical Center, Nijmegen, The Netherlands
- Dutch Expert Center for Screening (LRCB), Nijmegen, The Netherlands
| | - E C Simpson
- Department of Nuclear Physics, Research School of Physics, Australian National University, Canberra, Australia
| | - T Toshito
- Nagoya Proton Therapy Center, Nagoya, Japan
| | - D H Wright
- SLAC National Accelerator Laboratory, Stanford, CA, USA
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Sanderink WBG, Strobbe LJA, Bult P, Schlooz-Vries MS, Lardenoije S, Venderink DJ, Sechopoulos I, Karssemeijer N, Vreuls W, Mann RM. Minimally invasive breast cancer excision using the breast lesion excision system under ultrasound guidance. Breast Cancer Res Treat 2020; 184:37-43. [PMID: 32737712 PMCID: PMC7568696 DOI: 10.1007/s10549-020-05814-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 07/15/2020] [Indexed: 11/08/2022]
Abstract
Purpose To assess the feasibility of completely excising small breast cancers using the automated, image-guided, single-pass radiofrequency-based breast lesion excision system (BLES) under ultrasound (US) guidance. Methods From February 2018 to July 2019, 22 patients diagnosed with invasive carcinomas ≤ 15 mm at US and mammography were enrolled in this prospective, multi-center, ethics board-approved study. Patients underwent breast MRI to verify lesion size. BLES-based excision and surgery were performed during the same procedure. Histopathology findings from the BLES procedure and surgery were compared, and total excision findings were assessed. Results Of the 22 patients, ten were excluded due to the lesion being > 15 mm and/or being multifocal at MRI, and one due to scheduling issues. The remaining 11 patients underwent BLES excision. Mean diameter of excised lesions at MRI was 11.8 mm (range 8.0–13.9 mm). BLES revealed ten (90.9%) invasive carcinomas of no special type, and one (9.1%) invasive lobular carcinoma. Histopathological results were identical for the needle biopsy, BLES, and surgical specimens for all lesions. None of the BLES excisions were adequate. Margins were usually compromised on both sides of the specimen, indicating that the excised volume was too small. Margin assessment was good for all BLES specimens. One technical complication occurred (retrieval of an empty BLES basket, specimen retrieved during subsequent surgery). Conclusions BLES allows accurate diagnosis of small invasive breast carcinomas. However, BLES cannot be considered as a therapeutic device for small invasive breast carcinomas due to not achieving adequate excision.
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Affiliation(s)
- W B G Sanderink
- Department of Medical Imaging/Radiology, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | - L J A Strobbe
- Department of Surgical Oncology, Canisius-Wilhelmina Hospital, Nijmegen, The Netherlands
| | - P Bult
- Department of Pathology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - M S Schlooz-Vries
- Department of Surgery, Radboud University Medical Center, Nijmegen, The Netherlands
| | - S Lardenoije
- Department of Medical Imaging/Radiology, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | - D J Venderink
- Department of Radiology, Canisius-Wilhelmina Hospital, Nijmegen, The Netherlands
| | - I Sechopoulos
- Department of Medical Imaging/Radiology, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | - N Karssemeijer
- Department of Medical Imaging/Radiology, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | - W Vreuls
- Department of Pathology, Canisius-Wilhelmina Hospital, Nijmegen, The Netherlands
| | - R M Mann
- Department of Medical Imaging/Radiology, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands.
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Sanderink WBG, Caballo M, Strobbe LJA, Bult P, Vreuls W, Venderink DJ, Sechopoulos I, Karssemeijer N, Mann RM. Reliability of MRI tumor size measurements for minimal invasive treatment selection in small breast cancers. Eur J Surg Oncol 2020; 46:1463-1470. [PMID: 32536526 DOI: 10.1016/j.ejso.2020.04.038] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 04/06/2020] [Accepted: 04/19/2020] [Indexed: 01/18/2023] Open
Abstract
INTRODUCTION Due to the shift towards minimal invasive treatment, accurate tumor size estimation is essential for small breast cancers. The purpose of this study was to determine the reliability of MRI-based tumor size measurements with respect to clinical, histological and radiomics characteristics in small invasive or in situ carcinomas of the breast to select patients for minimal invasive therapy. MATERIALS AND METHODS All consecutive cases of cT1 invasive breast carcinomas that underwent pre-operative MRI, treated in two hospitals between 2005 and 2016, were identified retrospectively from the Dutch cancer registry and cross-correlated with local databases. Concordance between MRI-based measurements and final pathological size was analyzed. The influence of clinical, histological and radiomics characteristics on the accuracy of MRI size measurements were analyzed. RESULTS Analysis included 343 cT1 breast carcinomas in 336 patients (mean age, 55 years; range, 25-81 years). Overall correlation of MRI measurements with pathology was moderately strong (ρ = 0.530, P < 0.001), in 42 cases (12.2%) MRI underestimated the size with more than 5 mm. Underestimation occurs more often in grade 2 and grade 3 disease than in low grade invasive cancers. In DCIS the frequency of underestimation is higher than in invasive breast cancer. Unfortunately, none of the patient, imaging or biopsy characteristics appeared predictive for underestimation. CONCLUSION Size measurements of small breast cancers on breast MRI are within 5 mm of pathological size in 88% of patients. Nevertheless, underestimation cannot be adequately predicted, particularly for grade 2 and grade 3 tumors, which may hinder patient selection for minimal invasive therapy.
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Affiliation(s)
- W B G Sanderink
- Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
| | - M Caballo
- Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
| | - L J A Strobbe
- Department of Surgical Oncology, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands
| | - P Bult
- Department of Pathology, Radboud University Medical Center, Nijmegen, the Netherlands
| | - W Vreuls
- Department of Pathology, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands
| | - D J Venderink
- Department of Radiology, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands
| | - I Sechopoulos
- Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
| | - N Karssemeijer
- Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
| | - R M Mann
- Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Nijmegen, the Netherlands.
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Balta C, Bouwman RW, Sechopoulos I, Broeders MJM, Karssemeijer N, van Engen RE, Veldkamp WJH. Can a channelized Hotelling observer assess image quality in acquired mammographic images of an anthropomorphic breast phantom including image processing? Med Phys 2018; 46:714-725. [PMID: 30561108 DOI: 10.1002/mp.13342] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 11/20/2018] [Accepted: 11/30/2018] [Indexed: 12/28/2022] Open
Abstract
PURPOSE To study the feasibility of a channelized Hotelling observer (CHO) to predict human observer performance in detecting calcification-like signals in mammography images of an anthropomorphic breast phantom, as part of a quality control (QC) framework. METHODS A prototype anthropomorphic breast phantom with inserted gold disks of 0.25 mm diameter was imaged with two different digital mammography x-ray systems at four different dose levels. Regions of interest (ROIs) were extracted from the acquired processed and unprocessed images, signal-present and signal-absent. The ROIs were evaluated by a CHO using four different formulations of the difference of Gaussian (DoG) channel sets. Three human observers scored the ROIs in a two-alternative forced-choice experiment. We compared the human and the CHO performance on the simple task to detect calcification-like disks in ROIs with and without postprocessing. The proportion of correct responses of the human reader (PCH ) and the CHO (PCCHO ) was calculated and the correlation between the two was analyzed using a mixed-effect regression model. To address the signal location uncertainty, the impact of shifting the DoG channel sets in all directions up to two pixels was evaluated. Correlation results including the goodness of fit (r2 ) of PCH and PCCHO for all different parameters were evaluated. RESULTS Subanalysis by system yielded strong correlations between PCH and PCCHO , with r2 between PCH and PCCHO was found to be between 0.926 and 0.958 for the unshifted and between 0.759 and 0.938 for the shifted channel sets, respectively. However, the linear fit suggested a slight system dependence. PCCHO with shifted channel sets increased CHO performance but the correlation with humans was decreased. These correlations were not considerably affected by of the DoG channel set used. CONCLUSIONS There is potential for the CHO to be used in QC for the evaluation of detectability of calcification-like signals. The CHO can predict the PC of humans in images of calcification-like signals of two different systems. However, a global model to be used for all systems requires further investigation.
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Affiliation(s)
- C Balta
- Dutch Expert Centre for Screening (LRCB), Radboud University Medical Center, Wijchenseweg 101, 6538 SW, Nijmegen, The Netherlands.,Department of Radiology and Nuclear Medicine, Radboud University Medical Center, PO Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - R W Bouwman
- Dutch Expert Centre for Screening (LRCB), Radboud University Medical Center, Wijchenseweg 101, 6538 SW, Nijmegen, The Netherlands
| | - I Sechopoulos
- Dutch Expert Centre for Screening (LRCB), Radboud University Medical Center, Wijchenseweg 101, 6538 SW, Nijmegen, The Netherlands.,Department of Radiology and Nuclear Medicine, Radboud University Medical Center, PO Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - M J M Broeders
- Dutch Expert Centre for Screening (LRCB), Radboud University Medical Center, Wijchenseweg 101, 6538 SW, Nijmegen, The Netherlands.,Department for Health Evidence, Radboud University Medical Center, PO Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - N Karssemeijer
- Department of Radiology and Nuclear Medicine, Radboud University Medical Center, PO Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - R E van Engen
- Dutch Expert Centre for Screening (LRCB), Radboud University Medical Center, Wijchenseweg 101, 6538 SW, Nijmegen, The Netherlands
| | - W J H Veldkamp
- Department of Radiology, Leiden University Medical Centre, Albinusdreef 2, 2333 ZA, Leiden, The Netherlands
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Sarno A, Mettivier G, Lillo FD, Bliznakova K, Sechopoulos I, Russo P. Abstract ID: 203 Breast model validation for Monte Carlo evaluation of normalized glandular dose coefficients in mammography. Phys Med 2017. [DOI: 10.1016/j.ejmp.2017.09.109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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Mettivier G, Bliznakova K, Sechopoulos I, Boone JM, Di Lillo F, Sarno A, Castriconi R, Russo P. Evaluation of the BreastSimulator software platform for breast tomography. Phys Med Biol 2017; 62:6446-6466. [PMID: 28398906 DOI: 10.1088/1361-6560/aa6ca3] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The aim of this work was the evaluation of the software BreastSimulator, a breast x-ray imaging simulation software, as a tool for the creation of 3D uncompressed breast digital models and for the simulation and the optimization of computed tomography (CT) scanners dedicated to the breast. Eight 3D digital breast phantoms were created with glandular fractions in the range 10%-35%. The models are characterised by different sizes and modelled realistic anatomical features. X-ray CT projections were simulated for a dedicated cone-beam CT scanner and reconstructed with the FDK algorithm. X-ray projection images were simulated for 5 mono-energetic (27, 32, 35, 43 and 51 keV) and 3 poly-energetic x-ray spectra typically employed in current CT scanners dedicated to the breast (49, 60, or 80 kVp). Clinical CT images acquired from two different clinical breast CT scanners were used for comparison purposes. The quantitative evaluation included calculation of the power-law exponent, β, from simulated and real breast tomograms, based on the power spectrum fitted with a function of the spatial frequency, f, of the form S(f) = α/f β . The breast models were validated by comparison against clinical breast CT and published data. We found that the calculated β coefficients were close to that of clinical CT data from a dedicated breast CT scanner and reported data in the literature. In evaluating the software package BreastSimulator to generate breast models suitable for use with breast CT imaging, we found that the breast phantoms produced with the software tool can reproduce the anatomical structure of real breasts, as evaluated by calculating the β exponent from the power spectral analysis of simulated images. As such, this research tool might contribute considerably to the further development, testing and optimisation of breast CT imaging techniques.
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Affiliation(s)
- G Mettivier
- Dipartimento di Fisica 'Ettore Pancini', Università di Napoli Federico II, and INFN Sezione di Napoli, I-80126 Napoli, Italy
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Sechopoulos I. MO-DE-209-04: Radiation Dosimetry in Breast Tomosynthesis. Med Phys 2016. [DOI: 10.1118/1.4957240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Sechopoulos I. TU-AB-207-01: Introduction to Tomosynthesis. Med Phys 2015. [DOI: 10.1118/1.4925536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Agasthya G, D'Orsi C, D'Orsi E, Sechopoulos I. SU-D-204-03: A Study On the Impact of Decreased Breast Compression During Mammography On Perceived Pain, Breast Thickness and Tissue Coverage. Med Phys 2015. [DOI: 10.1118/1.4923897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Agasthya G, Sechopoulos I. TU-CD-207-09: Analysis of the 3-D Shape of Patients’ Breast for Breast Imaging and Surgery Planning. Med Phys 2015. [DOI: 10.1118/1.4925628] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Svahn TM, Houssami N, Sechopoulos I, Mattsson S. Review of radiation dose estimates in digital breast tomosynthesis relative to those in two-view full-field digital mammography. Breast 2015; 24:93-9. [PMID: 25554018 PMCID: PMC5064843 DOI: 10.1016/j.breast.2014.12.002] [Citation(s) in RCA: 143] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Revised: 11/25/2014] [Accepted: 12/03/2014] [Indexed: 11/23/2022] Open
Abstract
We examined how radiation dose levels in digital breast tomosynthesis (DBT) differ from those used in 2-view full-field digital mammography (FFDM). Acquisition parameter settings and information on the average absorbed dose to the glandular tissues within the breasts were reviewed based on clinical studies that evaluated DBT and FFDM. Dose ratios (DDBT/DFFDM) were derived from imaging protocols, which included tomosynthesis in 1- or 2-views alone, and as an adjunct technique to FFDM. Stand-alone DBT was associated with a much lower to a slightly higher radiation dose compared to that of comparable FFDM units, as summarized in dose ratio ranges of 0.34-1.0 for 1-view DBT, and 0.68-1.17 for 2-view DBT. One of the lowest reported dose estimates was obtained using a photon-counting DBT unit (avg. 0.70 mGy/scan; range: 0.28-1.26 mGy). Breast doses for DBT combined with FFDM are summarized in dose ratio ranges of 1.03-1.5 for 1-view DBT plus FFDM, and 2.0-2.23 for 2-view DBT plus FFDM. In the latter of these settings, the dose was reduced by ∼45% when 2D-views, reconstructed from the DBT images ("synthetic 2D images"), were used as a substitute for FFDM. Stand-alone DBT operated at lower to slightly higher radiation doses in comparison to FFDM. For DBT combined with FFDM, radiation doses were elevated, at maximum by a factor ∼2 1/4 of that of FFDM alone. In this setting, a replacement of FFDM with synthetic 2D-views reduced the breast dose approximately by half, which has substantial implications for population screening programs.
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Affiliation(s)
- T M Svahn
- School of Public Health, Sydney Medical School, University of Sydney, Sydney 2006, NSW, Australia.
| | - N Houssami
- School of Public Health, Sydney Medical School, University of Sydney, Sydney 2006, NSW, Australia
| | - I Sechopoulos
- Department of Radiology and Imaging Sciences, Emory University, 1701 Uppergate Drive Northeast, Suite 5018, Atlanta, GA 30322, USA; Department of Hematology and Medical Oncology, Emory University, 1701 Uppergate Drive Northeast, Suite 5018, Atlanta, GA 30322, USA; Winship Cancer Institute, Emory University, 1701 Uppergate Drive Northeast, Suite 5018, Atlanta, GA 30322, USA
| | - S Mattsson
- Medical Radiation Physics, Department of Clinical Sciences Malmö, Lund University, Skåne University Hospital, Malmö, Sweden
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Malliori A, Bliznakova K, Sechopoulos I, Kamarianakis Z, Fei B, Pallikarakis N. Breast tomosynthesis with monochromatic beams: a feasibility study using Monte Carlo simulations. Phys Med Biol 2014; 59:4681-96. [PMID: 25082791 DOI: 10.1088/0031-9155/59/16/4681] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The aim of this study is to investigate the impact on image quality of using monochromatic beams for lower dose breast tomosynthesis (BT). For this purpose, modeling and simulation of BT and mammography imaging processes have been performed using two x-ray beams: one at 28 kVp and a monochromatic one at 19 keV at different entrance surface air kerma ranging between 0.16 and 5.5 mGy. Two 4 cm thick computational breast models, in a compressed state, were used: one simple homogeneous and one heterogeneous based on CT breast images, with compositions of 50% glandular-50% adipose and 40% glandular-60% adipose tissues by weight, respectively. Modeled lesions, representing masses and calcifications, were inserted within these breast phantoms. X-ray transport in the breast models was simulated with previously developed and validated Monte Carlo application. Results showed that, for the same incident photon fluence, the use of the monochromatic beam in BT resulted in higher image quality compared to the one using polychromatic acquisition, especially in terms of contrast. For the homogenous phantom, the improvement ranged between 15% and 22% for calcifications and masses, respectively, while for the heterogeneous one this improvement was in the order of 33% for the masses and 17% for the calcifications. For different exposures, comparable image quality in terms of signal-difference-to-noise ratio and higher contrast for all features was obtained when using a monochromatic 19 keV beam at a lower mean glandular dose, compared to the polychromatic one. Monochromatic images also provide better detail and, in combination with BT, can lead to substantial improvement in visualization of features, and particularly better edge detection of low-contrast masses.
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Affiliation(s)
- A Malliori
- Department of Medical Physics, Faculty of Medicine, University of Patras, Patras 26500, Greece
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Ramamurthy S, Sechopoulos I. TU-F-18C-03: X-Ray Scatter Correction in Breast CT: Advances and Patient Testing. Med Phys 2014. [DOI: 10.1118/1.4889348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Badal A, Zbijewski W, Bolch W, Sechopoulos I. TH-E-18A-01: Developments in Monte Carlo Methods for Medical Imaging. Med Phys 2014. [DOI: 10.1118/1.4889651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Sechopoulos I, Fei B, Bliznakova K. WE-G-103-05: Spatial Frequency Characterization of the X-Ray Scatter Signal in Breast Imaging. Med Phys 2013. [DOI: 10.1118/1.4815665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Feng SSJ, Bliznakova K, Qin X, Fei B, Sechopoulos I. MO-F-213CD-08: Characterization of the Homogeneous Breast Tissue Mixture Approximation for Breast Image Dosimetry. Med Phys 2012. [DOI: 10.1118/1.4735833] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Feng SSJ, Sechopoulos I. SU-E-I-58: Objective Models of Breast Shape Undergoing Mammography and Tomosynthesis Using Principal Component Analysis. Med Phys 2012; 39:3638. [DOI: 10.1118/1.4734774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Sechopoulos I. WE-G-BRA-02: Visual Demonstrations of Medical Physics Concepts of Transmission Imaging for Resident Education. Med Phys 2012; 39:3969. [DOI: 10.1118/1.4736197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Abstract
PURPOSE To reduce the impact of x-ray scatter in dedicated breast computed tomography (BCT) images. METHODS The inclusion of x-ray scatter in BCT projections results in cupping artifacts, loss of contrast, and quantitative inaccuracies. To correct for this, an additional set of BCT projections is acquired with a tungsten plate placed between the x-ray source and the patient breast. The tungsten plate includes a two-dimensional grid of perforations to generate an array of pencil beams. Due to the limited area illuminated by the x-ray pencil beams, an array of signals of primary x-rays only is obtained. At the pencil beam locations, the difference between the plate projections and the standard projections is an estimate of the scatter present in the latter. These estimates are interpolated to obtain scatter-only estimates of the whole images, which are subtracted from the standard projections, resulting in BCT projections with primary signal only, which are then reconstructed. To reduce the impact of the quantum noise of the scatter signal, the resulting reconstructions are noise filtered. Monte Carlo simulations were performed to estimate the amount of scatter included in the pencil beams and the dose from these additional projections. The algorithm was tested using breast phantoms on a BCT clinical prototype system. RESULTS The maximum scatter signal in the pencil beams is 2.2% (mean of 0.7%) of the total signal, so the pencil beams are an excellent estimate of the primary-only signal. The additional projections Result in only 0.4% of the glandular dose of the standard projections. The homogeneity of the resulting phantom images, the signal difference between adipose and glandular tissue, reconstruction accuracy, and contrast-to-noise ratios were improved with this algorithm. CONCLUSIONS The proposed algorithm has the potential to substantially improve BCT image quality with practically no additional dose to the patient breast.
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Sprawls P, Monticciolo D, Sechopoulos I. WE-G-BRC-01: A Model for Clinically Focused Physics Education. Med Phys 2011. [DOI: 10.1118/1.3613416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Feng SSJ, Nagy J, Chung J, Mejia-Bustamante V, Sechopoulos I. SU-E-I-145: A Spectral Reconstruction Method for Digital Breast Tomosynthesis. Med Phys 2011. [DOI: 10.1118/1.3611719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Sechopoulos I, Abboud S, Ali E, Badal A, Badano A, Feng SSJ, Kyprianou I, McNitt-Gray M, Samei E, Turner A. WE-G-110-06: Introduction to the AAPM Task Group No. 195 - Monte Carlo Reference Data Sets for Imaging Research. Med Phys 2011. [DOI: 10.1118/1.3613436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Sechopoulos I, Feng SS. WE-A-201B-05: Dosimetric Characterization of a Dedicated Breast Computed Tomography Clinical Prototype System. Med Phys 2010. [DOI: 10.1118/1.3469337] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Sechopoulos I, Schmitz A, Eberhard JW. SU-GG-I-127: Characterization of Point Spread Functions of Indirect Digital Radiography Detectors. Med Phys 2010. [DOI: 10.1118/1.3468161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Sechopoulos I, Feng S. SU-FF-I-49: X-Ray Scatter Reduction in Tomosynthesis Imaging of the Breast. Med Phys 2009. [DOI: 10.1118/1.3181168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Sechopoulos I, Schmitz A, Eberhard J. SU-GG-I-93: A Fast and Simple Software-Based Method for X-Ray Scatter Reduction in Portable X-Ray Systems. Med Phys 2008. [DOI: 10.1118/1.2961491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Suryanarayanan S, Sechopoulos I, Vedantham S, Karellas A. SU-FF-I-97: Feasibility of Low Dose X-Ray Contrast Enhanced Digital Mammography with Gold Nanoparticles. Med Phys 2007. [DOI: 10.1118/1.2760474] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Vedantham S, Suryanarayanan S, Sechopoulos I, Karellas A. TH-C-L100F-10: Monte Carlo Coupled Modeling of a Computed Radiography System. Med Phys 2007. [DOI: 10.1118/1.2761637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Sechopoulos I, Suryanarayanan S, Vedantham S, D'Orsi CJ, Karellas A. WE-E-L100J-05: Radiation Dose to Tissues From Mammography. Med Phys 2007. [DOI: 10.1118/1.2761580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Sechopoulos I, Vedantham S, Suryanarayanan S, Karellas A. SU-FF-I-12: Validation of Geant4's Predictions On X-Ray Scatter and Glandular Dose in Pendant-Geometry Cone-Beam Breast CT. Med Phys 2006. [DOI: 10.1118/1.2240250] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Sechopoulos I, Suryanarayanan S, Vedantham S, Karellas A. SU-DD-A4-05: Characterization of X-Ray Scatter and Glandular Dose in Digital Tomosynthesis for Breast Imaging Using Monte Carlo Simulations. Med Phys 2006. [DOI: 10.1118/1.2240153] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Suryanarayanan S, Vedantham S, Sechopoulos I, Karellas A. WE-E-330D-03: Feasibility of High-Resolution Contrast Enhanced Digital Mammography. Med Phys 2006. [DOI: 10.1118/1.2241793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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