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Moshina N, Sagstad S, Holen ÅS, Backmann HA, Westermann LC, Hofvind S. Experience of pain during mammographic screening by three different compression paddles. Radiography (Lond) 2023; 29:903-910. [PMID: 37453253 DOI: 10.1016/j.radi.2023.06.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 06/22/2023] [Accepted: 06/23/2023] [Indexed: 07/18/2023]
Abstract
INTRODUCTION Experience of pain during screening mammography is shown to affect further attendance negatively. We aimed to explore the experience of pain during screening mammography using three different breast compression paddles. METHODS Using a self-report questionnaire, we collected information on pain experienced during mammography from 938 women screened in Bodø at Nordland Hospital County in 2018, as a part of BreastScreen Norway. Pain was assessed by a numeric rating scale (NRS, 0-10). A fixed paddle, a flexible paddle or a fixed paddle standardizing pressure (study paddle) were used during screening. Compression force (kg) was recorded by the radiographers for each screening examination. Log-binomial regression was used to determine the relative risk (RR) of severe (≥7 on NRS) versus mild/moderate (<7 on NRS) experience of pain associated with type of compression paddle, adjusting for breast tenderness, shoulder(s) and/or neck pain prior to screening, compression force, age, body mass index and screening history. RESULTS Mean score of self-reported experienced pain was 2.8 for the fixed, 2.3 for the flexible and 2.8 for the study paddle (p < 0.03 for fixed versus flexible and for flexible versus study paddle). Adjusted RR of severe pain was higher for the fixed (RRAdj 2.01, 95%CI 1.13-3.59) and the study paddle (RRAdj 2.52, 95%CI 1.44-4.42) compared to the flexible paddle. Breast tenderness was associated with a higher risk (RRAdj 1.93, 95%CI 1.04-3.58) of severe pain compared to no breast tenderness. CONCLUSION Women screened with the flexible paddle reported lower experience of pain than those screened with the fixed or study paddle. IMPLICATION FOR PRACTICE The flexible compression paddle might be the best choice regarding experience of pain in screening mammography. Breast tenderness should be considered by the radiographers in a practical screening setting.
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Affiliation(s)
- N Moshina
- Section for Breast Cancer Screening, Cancer Registry of Norway, Oslo, Norway.
| | - S Sagstad
- Section for Breast Cancer Screening, Cancer Registry of Norway, Oslo, Norway.
| | - Å S Holen
- Section for Breast Cancer Screening, Cancer Registry of Norway, Oslo, Norway.
| | - H A Backmann
- Department of Radiology, Nordland Hospital Trust, Bodø, Norway.
| | - L C Westermann
- Department of Radiology, Nordland Hospital Trust, Bodø, Norway.
| | - S Hofvind
- Section for Breast Cancer Screening, Cancer Registry of Norway, Oslo, Norway; Department of Health and Care Sciences, The Arctic University of Norway, Tromsø, Norway.
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Lee S, Kim H, Lee H, Cho S. Deep-learning-based projection-domain breast thickness estimation for shape-prior iterative image reconstruction in digital breast tomosynthesis. Med Phys 2022; 49:3670-3682. [PMID: 35297075 DOI: 10.1002/mp.15612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 03/10/2022] [Accepted: 03/11/2022] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND Digital breast tomosynthesis (DBT) is a technique that can overcome the shortcomings of conventional X-ray mammography and can be effective for the early screening of breast cancer. The compression of the breast is essential during the DBT imaging. However, since the periphery of the breast cannot be compressed to a constant value, nonuniformity of thickness and in-plane shape variation happen. These cause inconvenience in diagnosis, scatter correction, and breast density estimation. PURPOSE In this study, we propose a deep-learning-based methodology for projection-domain breast thickness estimation and demonstrate a shape-prior iterative DBT image reconstruction. METHODS We prepared the Euclidean distance map, the thickness map, and the thickness corrected image of the simulated breast projections for thickness and shape estimation. Each pixel of the Euclidean distance map denotes a distance to the closest skin-line. The thickness map is defined as a conceptual projection of ideal breast support that differentiates the inner and outer regions of the breast phantom. The thickness projection map thus represents the x-ray path lengths of a homogeneous breast phantom. We generated the thickness corrected image by dividing the projection image by the thickness map in a pixel-wise manner. We developed a convolutional neural network for thickness estimation and correction. The network utilizes a projection image and a Euclidean distance image together as a dual input. An estimated breast thickness map is then used for constructing the breast shape mask by use of the discrete algebraic reconstruction technique (DART). RESULTS The proposed network effectively corrected the breast thickness in various simulation situations. Low normalized root-mean-squared error (NRMSE; 1.976%) and high structural similarity (SSIM; 99.997%) indicated a good agreement between the network-generated thickness corrected image and the ground-truth image. Compared to the existing methods and simple single-input network, the proposed method showed outperformance in breast thickness estimation and accordingly in breast shape recovery for various numerical phantoms without provoking any significant artifact. We have demonstrated that the uniformity of voxel value has improved by the inclusion of a shape-prior for the iterative DBT reconstruction. CONCLUSIONS We presented a novel deep-learning-based breast thickness correction and a shape reconstruction method. This approach to estimating the true thickness map and the shape of the breast undergoing compression can benefit various fields such as improvement of diagnostic breast images, scatter correction, material decomposition, and breast density estimation. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Seoyoung Lee
- Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Korea
| | - Hyeongseok Kim
- KAIST Institute for Artificial Intelligence, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Korea
| | - Hoyeon Lee
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, 02114, USA
| | - Seungryong Cho
- Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Korea.,KAIST Institute for Artificial Intelligence, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Korea.,KAIST Institutes for IT Convergence and Health Science and Technology, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Korea
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Fowler EEE, Smallwood AM, Khan NZ, Kilpatrick K, Sellers TA, Heine J. Technical challenges in generalizing calibration techniques for breast density measurements. Med Phys 2019; 46:679-688. [PMID: 30525207 PMCID: PMC6367025 DOI: 10.1002/mp.13325] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 11/20/2018] [Accepted: 11/21/2018] [Indexed: 11/12/2022] Open
Abstract
PURPOSE We are developing a calibration methodology for full-field digital mammography (FFDM). Calibration compensates for image acquisition technique influences on the pixel representation, ideally producing improved inter-image breast density estimates. This approach relies on establishing references with rigid breast tissue-equivalent phantoms (BTEs) and requires an accurate estimate of the compressed breast thickness because the system readout is nominal. There is also an attenuation mismatch between adipose breast tissue and the adipose BTE that was noted in our previous work. It is referred to as the "attenuation anomaly" and addressed in this report. The objectives are to evaluate methods to correct for the compressed breast thickness and compensate for the attenuation anomaly. METHODS Thickness correction surfaces were established with a deformable phantom (DP) using both image and physical measurements for three direct x-ray conversion FFDM units. The Cumulative Sum serial quality control procedure was established to ensure the thickness correction measurements were stable over time by imaging and calibrating DPs biweekly in lieu of physical measurements. The attenuation anomaly was addressed by evaluating adipose image regions coupled with an optimization technique to adjust the adipose calibration data. We compared calibration consistency across matched left and right cranial caudal (CC) mammographic views (n = 199) with and without corrections using Bland-Altman plots. These plots were complemented by comparing the right and left breast calibrated average (μa ) and population distribution mean (ma ) with 95% confidence intervals and difference distribution variances with the F-test for uncorrected and corrected data. RESULTS Thickness correction surfaces were well approximated as tilted planes and were dependent upon compression force. A correction was developed for the attenuation anomaly. All paddles (large and small paddles for all units) exhibited similar tilt as a function of force. Without correction, ma = 0.92 (-1.77, 3.62) was not significantly different from zero with many negative μa samples. The thickness correction produced a significant shift in the μa distribution in the positive direction with ma = 13.99 (11.17, 16.80) and reduced the difference distribution variance significantly (P < 0.0001). Applying both corrections in tandem gave ma = 22.83 (20.32, 25.34), representing another significant positive shift in comparison with the thickness correction in isolation. Thickness corrections were stable over approximately a 2-year timeframe for all units. CONCLUSION These correction techniques are valid approaches for addressing technical problems with calibration that relies on reference phantoms. The efficacy of the calibration methodology will require validation with clinical endpoints in future studies.
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Affiliation(s)
- Erin E E Fowler
- Cancer Epidemiology Department, Moffitt Cancer Center & Research Institute, 12902 Bruce B. Downs Blvd, Tampa, FL, 33612, USA
| | - Autumn M Smallwood
- Corporate Compliance Department, Moffitt Cancer Center & Research Institute, 12902 Bruce B. Downs Blvd, Tampa, FL, 33612, USA
| | | | | | - Thomas A Sellers
- Cancer Epidemiology Department, Moffitt Cancer Center & Research Institute, 12902 Bruce B. Downs Blvd, Tampa, FL, 33612, USA
| | - John Heine
- Cancer Epidemiology Department, Moffitt Cancer Center & Research Institute, 12902 Bruce B. Downs Blvd, Tampa, FL, 33612, USA
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Rodríguez-Ruiz A, Agasthya GA, Sechopoulos I. The compressed breast during mammography and breast tomosynthesis: in vivo shape characterization and modeling. Phys Med Biol 2017; 62:6920-6937. [PMID: 28665291 DOI: 10.1088/1361-6560/aa7cd0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
To characterize and develop a patient-based 3D model of the compressed breast undergoing mammography and breast tomosynthesis. During this IRB-approved, HIPAA-compliant study, 50 women were recruited to undergo 3D breast surface imaging with structured light (SL) during breast compression, along with simultaneous acquisition of a tomosynthesis image. A pair of SL systems were used to acquire 3D surface images by projecting 24 different patterns onto the compressed breast and capturing their reflection off the breast surface in approximately 12-16 s. The 3D surface was characterized and modeled via principal component analysis. The resulting surface model was combined with a previously developed 2D model of projected compressed breast shapes to generate a full 3D model. Data from ten patients were discarded due to technical problems during image acquisition. The maximum breast thickness (found at the chest-wall) had an average value of 56 mm, and decreased 13% towards the nipple (breast tilt angle of 5.2°). The portion of the breast not in contact with the compression paddle or the support table extended on average 17 mm, 18% of the chest-wall to nipple distance. The outermost point along the breast surface lies below the midline of the total thickness. A complete 3D model of compressed breast shapes was created and implemented as a software application available for download, capable of generating new random realistic 3D shapes of breasts undergoing compression. Accurate characterization and modeling of the breast curvature and shape was achieved and will be used for various image processing and clinical tasks.
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Affiliation(s)
- Alejandro Rodríguez-Ruiz
- Department of Radiology and Nuclear Medicine, Radboud University Medical Centre, Geert Grooteplein 10, 6525 GA, Nijmegen, Netherlands
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He W, Hogg P, Juette A, Denton ERE, Zwiggelaar R. Breast image pre-processing for mammographic tissue segmentation. Comput Biol Med 2015; 67:61-73. [PMID: 26498046 DOI: 10.1016/j.compbiomed.2015.10.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 09/22/2015] [Accepted: 10/02/2015] [Indexed: 10/22/2022]
Abstract
During mammographic image acquisition, a compression paddle is used to even the breast thickness in order to obtain optimal image quality. Clinical observation has indicated that some mammograms may exhibit abrupt intensity change and low visibility of tissue structures in the breast peripheral areas. Such appearance discrepancies can affect image interpretation and may not be desirable for computer aided mammography, leading to incorrect diagnosis and/or detection which can have a negative impact on sensitivity and specificity of screening mammography. This paper describes a novel mammographic image pre-processing method to improve image quality for analysis. An image selection process is incorporated to better target problematic images. The processed images show improved mammographic appearances not only in the breast periphery but also across the mammograms. Mammographic segmentation and risk/density classification were performed to facilitate a quantitative and qualitative evaluation. When using the processed images, the results indicated more anatomically correct segmentation in tissue specific areas, and subsequently better classification accuracies were achieved. Visual assessments were conducted in a clinical environment to determine the quality of the processed images and the resultant segmentation. The developed method has shown promising results. It is expected to be useful in early breast cancer detection, risk-stratified screening, and aiding radiologists in the process of decision making prior to surgery and/or treatment.
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Affiliation(s)
- Wenda He
- Department of Computer Science, Aberystwyth University, Aberystwyth SY23 3DB, UK.
| | - Peter Hogg
- School of Health Sciences, University of Salford, Salford M6 6PU, UK.
| | - Arne Juette
- Department of Radiology, Norfolk & Norwich University Hospital, Norwich NR4 7UY, UK.
| | - Erika R E Denton
- Department of Radiology, Norfolk & Norwich University Hospital, Norwich NR4 7UY, UK.
| | - Reyer Zwiggelaar
- Department of Computer Science, Aberystwyth University, Aberystwyth SY23 3DB, UK.
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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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Morrish OWE, Tucker L, Black R, Willsher P, Duffy SW, Gilbert FJ. Mammographic breast density: comparison of methods for quantitative evaluation. Radiology 2015; 275:356-65. [PMID: 25559234 DOI: 10.1148/radiol.14141508] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To evaluate the results from two software tools for measurement of mammographic breast density and compare them with observer-based scores in a large cohort of women. MATERIALS AND METHODS Following written informed consent, a data set of 36 281 mammograms from 8867 women were collected from six United Kingdom centers in an ethically approved trial. Breast density was assessed by one of 26 readers on a visual analog scale and with two automated density tools. Mean differences were calculated as the mean of all the individual percentage differences between each measurement for each case (woman). Agreement in total breast volume, fibroglandular volume, and percentage density was assessed with the Bland-Altman method. Association with observer's scores was calculated by using the Pearson correlation coefficient (r). RESULTS Correlation between the Quantra and Volpara outputs for total breast volume was r = 0.97 (P < .001), with a mean difference of 43.5 cm(3) for all cases representing 5.0% of the mean total breast volume. Correlation of the two measures was lower for fibroglandular volume (r = 0.86, P < .001). The mean difference was 30.3 cm(3) for all cases representing 21.2% of the mean fibroglandular tissue volume result. Quantra gave the larger value and the difference tended to increase with volume. For the two measures of percentage volume density, the mean difference was 1.61 percentage points (r = 0.78, P < .001). Comparison of observer's scores with the area-based density given by Quantra yielded a low correlation (r = 0.55, P < .001). Correlations of observer's scores with the volumetric density results gave r values of 0.60 (P < .001) and 0.63 (P < .001) for Quantra and Volpara, respectively. CONCLUSION Automated techniques for measuring breast density show good correlation, but these are poorly correlated with observer's scores. However automated techniques do give different results that should be considered when informing patient personalized imaging. (©) RSNA, 2015 Clinical trial registration no. ISRCTN 73467396.
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Affiliation(s)
- Oliver W E Morrish
- From the East Anglian Regional Radiation Protection Service (O.W.E.M.), Department of Medical Physics and Clinical Engineering (R.B.), and Cambridge Breast Unit (P.W.), Cambridge University Hospitals NHS Foundation Trust, Cambridge, England; Department of Radiology, University of Cambridge School of Clinical Medicine, Cambridge Biomedical Campus, Cambridge CB2 0QQ, England (L.T., F.J.G.); and Wolfson Institute of Preventive Medicine, Queen Mary University of London, London, England (S.W.D.)
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Broeders MJM, Ten Voorde M, Veldkamp WJH, van Engen RE, van Landsveld-Verhoeven C, 't Jong-Gunneman MNL, de Win J, Greve KDD, Paap E, den Heeten GJ. Comparison of a flexible versus a rigid breast compression paddle: pain experience, projected breast area, radiation dose and technical image quality. Eur Radiol 2015; 25:821-9. [PMID: 25504427 PMCID: PMC4328113 DOI: 10.1007/s00330-014-3422-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 08/12/2014] [Accepted: 08/28/2014] [Indexed: 11/29/2022]
Abstract
PURPOSE To compare pain, projected breast area, radiation dose and image quality between flexible (FP) and rigid (RP) breast compression paddles. METHODS The study was conducted in a Dutch mammographic screening unit (288 women). To compare both paddles one additional image with RP was made, consisting of either a mediolateral-oblique (MLO) or craniocaudal-view (CC). Pain experience was scored using the Numeric Rating Scale (NRS). Projected breast area was estimated using computer software. Radiation dose was estimated using the model by Dance. Image quality was reviewed by three radiologists and three radiographers. RESULTS There was no difference in pain experience between both paddles (mean difference NRS: 0.08 ± 0.08, p = 0.32). Mean radiation dose was 4.5 % lower with FP (0.09 ± 0.01 p = 0.00). On MLO-images, the projected breast area was 0.79 % larger with FP. Paired evaluation of image quality indicated that FP removed fibroglandular tissue from the image area and reduced contrast in the clinically relevant retroglandular area at chest wall side. CONCLUSIONS Although FP performed slightly better in the projected breast area, it moved breast tissue from the image area at chest wall side. RP showed better contrast, especially in the retroglandular area. We therefore recommend the use of RP for standard MLO and CC views.
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Affiliation(s)
- Mireille J M Broeders
- Dutch Reference Centre for Screening, PO Box 6873, 6503 GJ, Nijmegen, The Netherlands,
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Tortajada M, Oliver A, Martí R, Ganau S, Tortajada L, Sentís M, Freixenet J, Zwiggelaar R. Breast peripheral area correction in digital mammograms. Comput Biol Med 2014; 50:32-40. [PMID: 24845018 DOI: 10.1016/j.compbiomed.2014.03.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Revised: 02/24/2014] [Accepted: 03/24/2014] [Indexed: 10/25/2022]
Abstract
Digital mammograms may present an overexposed area in the peripheral part of the breast, which is visually shown as a darker area with lower contrast. This has a direct impact on image quality and affects image visualisation and assessment. This paper presents an automatic method to enhance the overexposed peripheral breast area providing a more homogeneous and improved view of the whole mammogram. The method automatically restores the overexposed area by equalising the image using information from the intensity of non-overexposed neighbour pixels. The correction is based on a multiplicative model and on the computation of the distance map from the breast boundary. A total of 334 digital mammograms were used for evaluation. Mammograms before and after enhancement were evaluated by an expert using visual comparison. In 90.42% of the cases, the enhancement obtained improved visualisation compared to the original image in terms of contrast and detail. Moreover, results show that lesions found in the peripheral area after enhancement presented a more homogeneous intensity distribution. Hence, peripheral enhancement is shown to improve visualisation and will play a role in further development of CAD systems in mammography.
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Affiliation(s)
- Meritxell Tortajada
- Department of Computer Architecture and Technology, University of Girona, Girona, Spain.
| | - Arnau Oliver
- Department of Computer Architecture and Technology, University of Girona, Girona, Spain
| | - Robert Martí
- Department of Computer Architecture and Technology, University of Girona, Girona, Spain
| | - Sergi Ganau
- UDIAT-Centre Diagnòstic, Corporació Parc Taulí, 08208 Sabadell, Spain
| | - Lidia Tortajada
- UDIAT-Centre Diagnòstic, Corporació Parc Taulí, 08208 Sabadell, Spain
| | - Melcior Sentís
- UDIAT-Centre Diagnòstic, Corporació Parc Taulí, 08208 Sabadell, Spain
| | - Jordi Freixenet
- Department of Computer Architecture and Technology, University of Girona, Girona, Spain
| | - Reyer Zwiggelaar
- Department of Computer Science, Aberystwyth University, Aberystwyth SY23 3DB, UK
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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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Tromans CE, Cocker MR, Brady SM. Quantification and normalization of x-ray mammograms. Phys Med Biol 2012; 57:6519-40. [DOI: 10.1088/0031-9155/57/20/6519] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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12
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Kallenberg MGJ, van Gils CH, Lokate M, den Heeten GJ, Karssemeijer N. Effect of compression paddle tilt correction on volumetric breast density estimation. Phys Med Biol 2012; 57:5155-68. [PMID: 22842727 DOI: 10.1088/0031-9155/57/16/5155] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
For the acquisition of a mammogram, a breast is compressed between a compression paddle and a support table. When compression is applied with a flexible compression paddle, the upper plate may be tilted, which results in variation in breast thickness from the chest wall to the breast margin. Paddle tilt has been recognized as a major problem in volumetric breast density estimation methods. In previous work, we developed a fully automatic method to correct the image for the effect of compression paddle tilt. In this study, we investigated in three experiments the effect of paddle tilt and its correction on volumetric breast density estimation. Results showed that paddle tilt considerably affected accuracy of volumetric breast density estimation, but that effect could be reduced by tilt correction. By applying tilt correction, a significant increase in correspondence between mammographic density estimates and measurements on MRI was established. We argue that in volumetric breast density estimation, tilt correction is both feasible and essential when mammographic images are acquired with a flexible compression paddle.
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Affiliation(s)
- Michiel G J Kallenberg
- Department of Radiology, Radboud University Nijmegen Medical Centre, Geert Grooteplein Zuid 18, 6525 GA Nijmegen, the Netherlands.
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