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Denholm R, De Stavola BL, Hipwell JH, Doran SJ, Holly JMP, Folkerd E, Dowsett M, Leach MO, Hawkes DJ, Dos-Santos-Silva I. Circulating Growth and Sex Hormone Levels and Breast Tissue Composition in Young Nulliparous Women. Cancer Epidemiol Biomarkers Prev 2018; 27:1500-1508. [PMID: 30228153 DOI: 10.1158/1055-9965.epi-18-0036] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 04/30/2018] [Accepted: 09/07/2018] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Endogenous hormones are associated with breast cancer risk, but little is known about their role on breast tissue composition, a strong risk predictor. This study aims to investigate the relationship between growth and sex hormone levels and breast tissue composition in young nulliparous women. METHODS A cross-sectional study of 415 young (age ∼21.5 years) nulliparous women from an English prebirth cohort underwent a MRI examination of their breasts to estimate percent-water (a proxy for mammographic percent density) and provided a blood sample to measure plasma levels of growth factors (insulin-like growth factor-I, insulin-like growth factor-II, insulin growth factor-binding protein-3, growth hormone) and, if not on hormonal contraception (n = 117) sex hormones (dehydroepiandrosterone, androstenedione, testosterone, estrone, estadiol, sex hormone-binding globulin, prolactin). Testosterone (n = 330) and sex hormone-binding globulin (n = 318) were also measured at age 15.5 years. Regression models were used to estimate the relative difference (RD) in percent-water associated with one SD increment in hormone levels. RESULTS Estradiol at age 21.5 and sex hormone-binding globulin at age 21.5 were positively associated with body mass index (BMI)-adjusted percent-water [RD (95% confidence interval (CI)): 3% (0%-7%) and 3% (1%-5%), respectively]. There was a positive nonlinear association between androstenedione at age 21.5 and percent-water. Insulin-like growth factor-I and growth hormone at age 21.5 were also positively associated with BMI-adjusted percent-water [RD (95% CI): 2% (0%-4%) and 4% (1%-7%), respectively]. CONCLUSIONS The findings suggest that endogenous hormones affect breast tissue composition in young nulliparous women. IMPACT The well-established associations of childhood growth and development with breast cancer risk may be partly mediated by the role of endogenous hormones on breast tissue composition.
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Affiliation(s)
- Rachel Denholm
- Department of Non-Communicable Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Bianca L De Stavola
- Population, Policy and Practice Programme, UCL Great Ormond Street Institute of Child Health, London, United Kingdom
| | - John H Hipwell
- Centre for Medical Image Computing, Department of Medical Physics and Bioengineering, UCL, London, United Kingdom
| | - Simon J Doran
- Cancer Research UK Cancer Imaging Centre, The Institute of Cancer Research and Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Jeff M P Holly
- IGFs & Metabolic Endocrinology Group, School of Translational Health Sciences, Faculty of Health Sciences, University of Bristol, Bristol, United Kingdom
| | - Elizabeth Folkerd
- The Ralph Lauren Centre for Breast Cancer Research, The Royal Marsden NHS Foundation Trust and Institute of Cancer Research, London, United Kingdom
| | - Mitch Dowsett
- The Ralph Lauren Centre for Breast Cancer Research, The Royal Marsden NHS Foundation Trust and Institute of Cancer Research, London, United Kingdom
| | - Martin O Leach
- Cancer Research UK Cancer Imaging Centre, The Institute of Cancer Research and Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - David J Hawkes
- Centre for Medical Image Computing, Department of Medical Physics and Bioengineering, UCL, London, United Kingdom
| | - Isabel Dos-Santos-Silva
- Department of Non-Communicable Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, United Kingdom.
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2
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Denholm R, De Stavola B, Hipwell JH, Doran SJ, Busana MC, Leach MO, Hawkes DJ, dos-Santos-Silva I. Growth Trajectories, Breast Size, and Breast-Tissue Composition in a British Prebirth Cohort of Young Women. Am J Epidemiol 2018; 187:1259-1268. [PMID: 29140420 PMCID: PMC5982787 DOI: 10.1093/aje/kwx358] [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] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2017] [Revised: 10/25/2017] [Accepted: 11/01/2017] [Indexed: 11/14/2022] Open
Abstract
Mammographic percent density, the proportion of fibroglandular tissue in the breast, is a strong risk factor for breast cancer, but its determinants in young women are unknown. We examined associations of magnetic resonance imaging (MRI) breast-tissue composition at age 21 years with prospectively collected measurements of body size and composition from birth to early adulthood and markers of puberty (all standardized) in a sample of 500 nulliparous women from a prebirth cohort of children born in Avon, United Kingdom, in 1991-1992 and followed up to 2011-2014. Linear models were fitted to estimate relative change in MRI percent water, which is equivalent to mammographic percent density, associated with a 1-standard-deviation increase in the exposure of interest. In mutually adjusted analyses, MRI percent water was positively associated with birth weight (relative change (RC) = 1.03, 95% confidence interval (CI): 1.00, 1.06) and pubertal height growth (RC = 1.07, 95% CI: 1.02, 1.13) but inversely associated with pubertal weight growth (RC = 0.86, 95% CI: 0.84, 0.89) and changes in dual-energy x-ray absorptiometry percent body fat mass (e.g., for change between ages 11 years and 13.5 years, RC = 0.96, 95% CI: 0.93, 0.99). Ages at thelarche and menarche were positively associated with MRI percent water, but these associations did not persist upon adjustment for height and weight growth. These findings support the hypothesis that growth trajectories influence breast-tissue composition in young women, whereas puberty plays no independent role.
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Affiliation(s)
- Rachel Denholm
- Department of Non-Communicable Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Bianca De Stavola
- Department of Medical Statistics, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - John H Hipwell
- Center for Medical Image Computing, Department of Medical Physics and Bioengineering, University College London, London, United Kingdom
| | - Simon J Doran
- Cancer Research UK Cancer Imaging Center, Institute of Cancer Research and Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Marta C Busana
- Department of Non-Communicable Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Martin O Leach
- Cancer Research UK Cancer Imaging Center, Institute of Cancer Research and Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - David J Hawkes
- Center for Medical Image Computing, Department of Medical Physics and Bioengineering, University College London, London, United Kingdom
| | - Isabel dos-Santos-Silva
- Department of Non-Communicable Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
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3
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Reis S, Gazinska P, Hipwell JH, Mertzanidou T, Naidoo K, Williams N, Pinder S, Hawkes DJ. Automated Classification of Breast Cancer Stroma Maturity From Histological Images. IEEE Trans Biomed Eng 2017; 64:2344-2352. [PMID: 28186876 DOI: 10.1109/tbme.2017.2665602] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
OBJECTIVE The tumor microenvironment plays a crucial role in regulating tumor progression by a number of different mechanisms, in particular, the remodeling of collagen fibers in tumor-associated stroma, which has been reported to be related to patient survival. The underlying motivation of this work is that remodeling of collagen fibers gives rise to observable patterns in hematoxylin and eosin (H&E) stained slides from clinical cases of invasive breast carcinoma that the pathologist can label as mature or immature stroma. The aim of this paper is to categorise and automatically classify stromal regions according to their maturity and show that this classification agrees with that of skilled observers, hence providing a repeatable and quantitative measure for prognostic studies. METHODS We use multiscale basic image features and local binary patterns, in combination with a random decision trees classifier for classification of breast cancer stroma regions-of-interest (ROI). RESULTS We present results from a cohort of 55 patients with analysis of 169 ROI. Our multiscale approach achieved a classification accuracy of 84%. CONCLUSION This work demonstrates the ability of texture-based image analysis to differentiate breast cancer stroma maturity in clinically acquired H&E-stained slides at least as well as skilled observers.
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Wijeratne PA, Hipwell JH, Hawkes DJ, Stylianopoulos T, Vavourakis V. Multiscale biphasic modelling of peritumoural collagen microstructure: The effect of tumour growth on permeability and fluid flow. PLoS One 2017; 12:e0184511. [PMID: 28902902 PMCID: PMC5597211 DOI: 10.1371/journal.pone.0184511] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 08/27/2017] [Indexed: 11/18/2022] Open
Abstract
We present an in-silico model of avascular poroelastic tumour growth coupled with a multiscale biphasic description of the tumour–host environment. The model is specified to in-vitro data, facilitating biophysically realistic simulations of tumour spheroid growth into a dense collagen hydrogel. We use the model to first confirm that passive mechanical remodelling of collagen fibres at the tumour boundary is driven by solid stress, and not fluid pressure. The model is then used to demonstrate the influence of collagen microstructure on peritumoural permeability and interstitial fluid flow. Our model suggests that at the tumour periphery, remodelling causes the peritumoural stroma to become more permeable in the circumferential than radial direction, and the interstitial fluid velocity is found to be dependent on initial collagen alignment. Finally we show that solid stresses are negatively correlated with peritumoural permeability, and positively correlated with interstitial fluid velocity. These results point to a heterogeneous, microstructure-dependent force environment at the tumour–peritumoural stroma interface.
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Affiliation(s)
- Peter A. Wijeratne
- Department of Computer Science, University College London, London, United Kingdom
- * E-mail:
| | - John H. Hipwell
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - David J. Hawkes
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | | | - Vasileios Vavourakis
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
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Doran SJ, Hipwell JH, Denholm R, Eiben B, Busana M, Hawkes DJ, Leach MO, Silva IDS. Breast MRI segmentation for density estimation: Do different methods give the same results and how much do differences matter? Med Phys 2017; 44:4573-4592. [PMID: 28477346 PMCID: PMC5697622 DOI: 10.1002/mp.12320] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 03/02/2017] [Accepted: 04/03/2017] [Indexed: 11/20/2022] Open
Abstract
PURPOSE To compare two methods of automatic breast segmentation with each other and with manual segmentation in a large subject cohort. To discuss the factors involved in selecting the most appropriate algorithm for automatic segmentation and, in particular, to investigate the appropriateness of overlap measures (e.g., Dice and Jaccard coefficients) as the primary determinant in algorithm selection. METHODS Two methods of breast segmentation were applied to the task of calculating MRI breast density in 200 subjects drawn from the Avon Longitudinal Study of Parents and Children, a large cohort study with an MRI component. A semiautomated, bias-corrected, fuzzy C-means (BC-FCM) method was combined with morphological operations to segment the overall breast volume from in-phase Dixon images. The method makes use of novel, problem-specific insights. The resulting segmentation mask was then applied to the corresponding Dixon water and fat images, which were combined to give Dixon MRI density values. Contemporaneously acquired T1 - and T2 -weighted image datasets were analyzed using a novel and fully automated algorithm involving image filtering, landmark identification, and explicit location of the pectoral muscle boundary. Within the region found, fat-water discrimination was performed using an Expectation Maximization-Markov Random Field technique, yielding a second independent estimate of MRI density. RESULTS Images are presented for two individual women, demonstrating how the difficulty of the problem is highly subject-specific. Dice and Jaccard coefficients comparing the semiautomated BC-FCM method, operating on Dixon source data, with expert manual segmentation are presented. The corresponding results for the method based on T1 - and T2 -weighted data are slightly lower in the individual cases shown, but scatter plots and interclass correlations for the cohort as a whole show that both methods do an excellent job in segmenting and classifying breast tissue. CONCLUSIONS Epidemiological results demonstrate that both methods of automated segmentation are suitable for the chosen application and that it is important to consider a range of factors when choosing a segmentation algorithm, rather than focus narrowly on a single metric such as the Dice coefficient.
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Affiliation(s)
- Simon J. Doran
- Division of Radiotherapy and Imaging, The Institute of Cancer ResearchCancer Research UK Cancer Imaging CentreLondonSM2 5NGUK
| | - John H. Hipwell
- Department of Medical Physics and BioengineeringUCL, Centre for Medical Image Computing (CMIC)LondonWC1E 7JEUK
| | - Rachel Denholm
- Department of Non‐Communicable Disease EpidemiologyLondon School of Hygiene & Tropical MedicineLondonWC1E 7HTUK
| | - Björn Eiben
- Department of Medical Physics and BioengineeringUCL, Centre for Medical Image Computing (CMIC)LondonWC1E 7JEUK
| | - Marta Busana
- Department of Non‐Communicable Disease EpidemiologyLondon School of Hygiene & Tropical MedicineLondonWC1E 7HTUK
| | - David J. Hawkes
- Department of Medical Physics and BioengineeringUCL, Centre for Medical Image Computing (CMIC)LondonWC1E 7JEUK
| | - Martin O. Leach
- Division of Radiotherapy and Imaging, The Institute of Cancer ResearchCancer Research UK Cancer Imaging CentreLondonSM2 5NGUK
| | - Isabel dos Santos Silva
- Department of Non‐Communicable Disease EpidemiologyLondon School of Hygiene & Tropical MedicineLondonWC1E 7HTUK
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Mertzanidou T, Hipwell JH, Reis S, Hawkes DJ, Ehteshami Bejnordi B, Dalmis M, Vreemann S, Platel B, van der Laak J, Karssemeijer N, Hermsen M, Bult P, Mann R. 3D volume reconstruction from serial breast specimen radiographs for mapping between histology and 3D whole specimen imaging. Med Phys 2017; 44:935-948. [PMID: 28064435 PMCID: PMC6849622 DOI: 10.1002/mp.12077] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Revised: 11/10/2016] [Accepted: 12/18/2016] [Indexed: 11/11/2022] Open
Abstract
PURPOSE In breast imaging, radiological in vivo images, such as x-ray mammography and magnetic resonance imaging (MRI), are used for tumor detection, diagnosis, and size determination. After excision, the specimen is typically sliced into slabs and a small subset is sampled. Histopathological imaging of the stained samples is used as the gold standard for characterization of the tumor microenvironment. A 3D volume reconstruction of the whole specimen from the 2D slabs could facilitate bridging the gap between histology and in vivo radiological imaging. This task is challenging, however, due to the large deformation that the breast tissue undergoes after surgery and the significant undersampling of the specimen obtained in histology. In this work, we present a method to reconstruct a coherent 3D volume from 2D digital radiographs of the specimen slabs. METHODS To reconstruct a 3D breast specimen volume, we propose the use of multiple target neighboring slices, when deforming each 2D slab radiograph in the volume, rather than performing pairwise registrations. The algorithm combines neighborhood slice information with free-form deformations, which enables a flexible, nonlinear deformation to be computed subject to the constraint that a coherent 3D volume is obtained. The neighborhood information provides adequate constraints, without the need for any additional regularization terms. RESULTS The volume reconstruction algorithm is validated on clinical mastectomy samples using a quantitative assessment of the volume reconstruction smoothness and a comparison with a whole specimen 3D image acquired for validation before slicing. Additionally, a target registration error of 5 mm (comparable to the specimen slab thickness of 4 mm) was obtained for five cases. The error was computed using manual annotations from four observers as gold standard, with interobserver variability of 3.4 mm. Finally, we illustrate how the reconstructed volumes can be used to map histology images to a 3D specimen image of the whole sample (either MRI or CT). CONCLUSIONS Qualitative and quantitative assessment has illustrated the benefit of using our proposed methodology to reconstruct a coherent specimen volume from serial slab radiographs. To our knowledge, this is the first method that has been applied to clinical breast cases, with the goal of reconstructing a whole specimen sample. The algorithm can be used as part of the pipeline of mapping histology images to ex vivo and ultimately in vivo radiological images of the breast.
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Affiliation(s)
- Thomy Mertzanidou
- Centre for Medical Image ComputingUniversity College LondonWC1E 6BTLondonUK
| | - John H. Hipwell
- Centre for Medical Image ComputingUniversity College LondonWC1E 6BTLondonUK
| | - Sara Reis
- Centre for Medical Image ComputingUniversity College LondonWC1E 6BTLondonUK
| | - David J. Hawkes
- Centre for Medical Image ComputingUniversity College LondonWC1E 6BTLondonUK
| | | | - Mehmet Dalmis
- Diagnostic Image Analysis GroupRadboud University Medical Center6500 HBNijmegenThe Netherlands
| | - Suzan Vreemann
- Diagnostic Image Analysis GroupRadboud University Medical Center6500 HBNijmegenThe Netherlands
| | - Bram Platel
- Diagnostic Image Analysis GroupRadboud University Medical Center6500 HBNijmegenThe Netherlands
| | - Jeroen van der Laak
- Diagnostic Image Analysis GroupRadboud University Medical Center6500 HBNijmegenThe Netherlands
| | - Nico Karssemeijer
- Diagnostic Image Analysis GroupRadboud University Medical Center6500 HBNijmegenThe Netherlands
| | - Meyke Hermsen
- Department of PathologyRadboud University Medical Center6500 HBNijmegenThe Netherlands
| | - Peter Bult
- Department of PathologyRadboud University Medical Center6500 HBNijmegenThe Netherlands
| | - Ritse Mann
- Department of RadiologyRadboud University Medical Center6500 HBNijmegenThe Netherlands
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7
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Bailey C, Siow B, Panagiotaki E, Hipwell JH, Mertzanidou T, Owen J, Gazinska P, Pinder SE, Alexander DC, Hawkes DJ. Microstructural models for diffusion MRI in breast cancer and surrounding stroma: an ex vivo study. NMR Biomed 2017; 30:e3679. [PMID: 28000292 PMCID: PMC5244665 DOI: 10.1002/nbm.3679] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 11/06/2016] [Accepted: 11/07/2016] [Indexed: 05/17/2023]
Abstract
The diffusion signal in breast tissue has primarily been modelled using apparent diffusion coefficient (ADC), intravoxel incoherent motion (IVIM) and diffusion tensor (DT) models, which may be too simplistic to describe the underlying tissue microstructure. Formalin-fixed breast cancer samples were scanned using a wide range of gradient strengths, durations, separations and orientations. A variety of one- and two-compartment models were tested to determine which best described the data. Models with restricted diffusion components and anisotropy were selected in most cancerous regions and there were no regions in which conventional ADC or DT models were selected. Maps of ADC generally related to cellularity on histology, but maps of parameters from more complex models suggest that both overall cell volume fraction and individual cell size can contribute to the diffusion signal, affecting the specificity of ADC to the tissue microstructure. The areas of coherence in diffusion anisotropy images were small, approximately 1 mm, but the orientation corresponded to stromal orientation patterns on histology.
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Affiliation(s)
- Colleen Bailey
- University College LondonCentre for Medical Image ComputingLondonUK
| | - Bernard Siow
- University College LondonCentre for Advanced Biomedical ImagingLondonUK
| | | | - John H. Hipwell
- University College LondonCentre for Medical Image ComputingLondonUK
| | | | - Julie Owen
- King's College LondonGuy's Hospital, Breast ResearchPathologyLondonUK
| | - Patrycja Gazinska
- King's College LondonGuy's Hospital, Breast ResearchPathologyLondonUK
| | - Sarah E. Pinder
- King's College LondonGuy's Hospital, Breast ResearchPathologyLondonUK
| | | | - David J. Hawkes
- University College LondonCentre for Medical Image ComputingLondonUK
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8
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Burton A, Byrnes G, Stone J, Tamimi RM, Heine J, Vachon C, Ozmen V, Pereira A, Garmendia ML, Scott C, Hipwell JH, Dickens C, Schüz J, Aribal ME, Bertrand K, Kwong A, Giles GG, Hopper J, Pérez Gómez B, Pollán M, Teo SH, Mariapun S, Taib NAM, Lajous M, Lopez-Riduara R, Rice M, Romieu I, Flugelman AA, Ursin G, Qureshi S, Ma H, Lee E, Sirous R, Sirous M, Lee JW, Kim J, Salem D, Kamal R, Hartman M, Miao H, Chia KS, Nagata C, Vinayak S, Ndumia R, van Gils CH, Wanders JOP, Peplonska B, Bukowska A, Allen S, Vinnicombe S, Moss S, Chiarelli AM, Linton L, Maskarinec G, Yaffe MJ, Boyd NF, dos-Santos-Silva I, McCormack VA. Mammographic density assessed on paired raw and processed digital images and on paired screen-film and digital images across three mammography systems. Breast Cancer Res 2016; 18:130. [PMID: 27993168 PMCID: PMC5168805 DOI: 10.1186/s13058-016-0787-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Accepted: 11/23/2016] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Inter-women and intra-women comparisons of mammographic density (MD) are needed in research, clinical and screening applications; however, MD measurements are influenced by mammography modality (screen film/digital) and digital image format (raw/processed). We aimed to examine differences in MD assessed on these image types. METHODS We obtained 1294 pairs of images saved in both raw and processed formats from Hologic and General Electric (GE) direct digital systems and a Fuji computed radiography (CR) system, and 128 screen-film and processed CR-digital pairs from consecutive screening rounds. Four readers performed Cumulus-based MD measurements (n = 3441), with each image pair read by the same reader. Multi-level models of square-root percent MD were fitted, with a random intercept for woman, to estimate processed-raw MD differences. RESULTS Breast area did not differ in processed images compared with that in raw images, but the percent MD was higher, due to a larger dense area (median 28.5 and 25.4 cm2 respectively, mean √dense area difference 0.44 cm (95% CI: 0.36, 0.52)). This difference in √dense area was significant for direct digital systems (Hologic 0.50 cm (95% CI: 0.39, 0.61), GE 0.56 cm (95% CI: 0.42, 0.69)) but not for Fuji CR (0.06 cm (95% CI: -0.10, 0.23)). Additionally, within each system, reader-specific differences varied in magnitude and direction (p < 0.001). Conversion equations revealed differences converged to zero with increasing dense area. MD differences between screen-film and processed digital on the subsequent screening round were consistent with expected time-related MD declines. CONCLUSIONS MD was slightly higher when measured on processed than on raw direct digital mammograms. Comparisons of MD on these image formats should ideally control for this non-constant and reader-specific difference.
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Affiliation(s)
- Anya Burton
- Section of Environment and Radiation, International Agency for Research on Cancer, 150 cours Albert Thomas, 69372 Lyon, Cedex 09, France
| | - Graham Byrnes
- Section of Environment and Radiation, International Agency for Research on Cancer, 150 cours Albert Thomas, 69372 Lyon, Cedex 09, France
| | - Jennifer Stone
- Centre for Genetic Origins of Health and Disease, Curtin University and the University of Western Australia, Perth, Australia
| | - Rulla M. Tamimi
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA USA
| | | | - Celine Vachon
- Department of Health Sciences Research, Mayo Clinic, Rochester, MN USA
| | - Vahit Ozmen
- Department of Surgery, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Ana Pereira
- Institute of Nutrition and Food Technology, University of Chile, Santiago, Chile
| | | | - Christopher Scott
- Department of Health Sciences Research, Mayo Clinic, Rochester, MN USA
| | - John H. Hipwell
- Centre for Medical Image Computing, University College London, London, UK
| | - Caroline Dickens
- Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Joachim Schüz
- Section of Environment and Radiation, International Agency for Research on Cancer, 150 cours Albert Thomas, 69372 Lyon, Cedex 09, France
| | | | | | - Ava Kwong
- Division of Breast Surgery, Department of Surgery, The University of Hong Kong, Hong Kong, People’s Republic of China
- Department of Surgery, Hong Kong Sanatorium and Hospital, Hong Kong, People’s Republic of China
| | - Graham G. Giles
- Cancer Epidemiology Centre, Cancer Council Victoria, Melbourne, Victoria Australia
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Victoria Australia
| | - John Hopper
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Victoria Australia
| | - Beatriz Pérez Gómez
- Cancer Epidemiology Unit, Instituto de Salud Carlos III and CIBERESP, Madrid, Spain
| | - Marina Pollán
- Cancer Epidemiology Unit, Instituto de Salud Carlos III and CIBERESP, Madrid, Spain
| | - Soo-Hwang Teo
- Breast Cancer Research Group, University Malaya Medical Centre, University Malaya, Kuala Lumpur, Malaysia
- Cancer Research Malaysia, Subang Jaya, Malaysia
| | | | - Nur Aishah Mohd Taib
- Breast Cancer Research Group, University Malaya Medical Centre, University Malaya, Kuala Lumpur, Malaysia
| | - Martín Lajous
- Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Boston, MA USA
- Center for Research on Population Health, Instituto Nacional de Salud Pública, Mexico City, Mexico
| | - Ruy Lopez-Riduara
- Center for Research on Population Health, Instituto Nacional de Salud Pública, Mexico City, Mexico
| | - Megan Rice
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA USA
| | - Isabelle Romieu
- Section of Nutrition and Metabolism, International Agency for Research on Cancer, Lyon, France
| | | | - Giske Ursin
- Cancer Registry of Norway, Oslo, Norway
- Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
- Department of Preventive Medicine, University of Southern California, Los Angeles, CA USA
| | - Samera Qureshi
- Norwegian Center for Minority and Migrant Health Research (NAKMI), Oslo, Norway
| | - Huiyan Ma
- Department of Population Sciences, Beckman Research Institute, City of Hope, CA USA
| | - Eunjung Lee
- Department of Preventive Medicine, University of Southern California, Los Angeles, CA USA
| | - Reza Sirous
- Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mehri Sirous
- Isfahan University of Medical Sciences, Isfahan, Iran
| | - Jong Won Lee
- Department of Surgery, Asan Medical Center, Seoul, Republic of Korea
| | - Jisun Kim
- Department of Surgery, Asan Medical Center, Seoul, Republic of Korea
| | | | - Rasha Kamal
- Woman Imaging Unit, Radiodiagnosis Department, Kasr El Aini, Cairo University Hospitals, Cairo, Egypt
| | - Mikael Hartman
- Department of Surgery, Yong Loo Lin School of Medicine, Singapore, Singapore
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
| | - Hui Miao
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
| | - Kee-Seng Chia
- NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore, Singapore
| | | | | | - Rose Ndumia
- Aga Khan University Hospital, Nairobi, Kenya
| | - Carla H. van Gils
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Johanna O. P. Wanders
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, The Netherlands
| | | | | | - Steve Allen
- Department of Imaging, Royal Marsden NHS Foundation Trust, London, UK
| | - Sarah Vinnicombe
- Division of Cancer Research, Ninewells Hospital & Medical School, Dundee, UK
| | - Sue Moss
- Wolfson Institute of Preventive Medicine, Queen Mary University of London, London, UK
| | - Anna M. Chiarelli
- Ontario Breast Screening Program, Cancer Care Ontario, Toronto, Canada
| | - Linda Linton
- Princess Margaret Cancer Centre, Toronto, Canada
| | | | | | | | - Isabel dos-Santos-Silva
- Department of Non-Communicable Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
| | - Valerie A. McCormack
- Section of Environment and Radiation, International Agency for Research on Cancer, 150 cours Albert Thomas, 69372 Lyon, Cedex 09, France
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Denholm R, De Stavola B, Hipwell JH, Doran SJ, Busana MC, Eng A, Jeffreys M, Leach MO, Hawkes D, dos Santos Silva I. Pre-natal exposures and breast tissue composition: findings from a British pre-birth cohort of young women and a systematic review. Breast Cancer Res 2016; 18:102. [PMID: 27729066 PMCID: PMC5059986 DOI: 10.1186/s13058-016-0751-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 08/23/2016] [Indexed: 12/01/2022] Open
Abstract
BACKGROUND Breast density, the amount of fibroglandular tissue in the adult breast for a women's age and body mass index, is a strong biomarker of susceptibility to breast cancer, which may, like breast cancer risk itself, be influenced by events early in life. In the present study, we investigated the association between pre-natal exposures and breast tissue composition. METHODS A sample of 500 young, nulliparous women (aged approximately 21 years) from a U.K. pre-birth cohort underwent a magnetic resonance imaging examination of their breasts to estimate percent water, a measure of the relative amount of fibroglandular tissue equivalent to mammographic percent density. Information on pre-natal exposures was collected throughout the mothers' pregnancy and shortly after delivery. Regression models were used to investigate associations between percent water and pre-natal exposures. Mediation analysis, and a systematic review and meta-analysis of the published literature, were also conducted. RESULTS Adjusted percent water in young women was positively associated with maternal height (p for linear trend [p t] = 0.005), maternal mammographic density in middle age (p t = 0.018) and the participant's birth size (p t < 0.001 for birthweight). A 1-SD increment in weight (473 g), length (2.3 cm), head circumference (1.2 cm) and Ponderal Index (4.1 g/cm3) at birth were associated with 3 % (95 % CI 2-5 %), 2 % (95 % CI 0-3 %), 3 % (95 % CI 1-4 %) and 1 % (95 % CI 0-3 %), respectively, increases in mean adjusted percent water. The effect of maternal height on the participants' percent water was partly mediated through birth size, but there was little evidence that the effect of birthweight was primarily mediated via adult body size. The meta-analysis supported the study findings, with breast density being positively associated with birth size. CONCLUSIONS These findings provide strong evidence of pre-natal influences on breast tissue composition. The positive association between birth size and relative amount of fibroglandular tissue indicates that breast density and breast cancer risk may share a common pre-natal origin.
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Affiliation(s)
- Rachel Denholm
- Department of Non-Communicable Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
| | - Bianca De Stavola
- Department of Medical Statistics, London School of Hygiene & Tropical Medicine, London, UK
| | - John H. Hipwell
- Centre for Medical Image Computing, Department of Medical Physics and Bioengineering, UCL, London, UK
| | - Simon J. Doran
- Cancer Research UK Cancer Imaging Centre, The Institute of Cancer Research (ICH) and Royal Marsden NHS Foundation Trust (RHM), London, UK
| | - Marta C. Busana
- Department of Non-Communicable Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
| | - Amanda Eng
- Centre for Public Health Research, Massey University, Wellington, New Zealand
| | - Mona Jeffreys
- School of Social and Community Medicine, University of Bristol, Bristol, UK
| | - Martin O. Leach
- Cancer Research UK Cancer Imaging Centre, The Institute of Cancer Research (ICH) and Royal Marsden NHS Foundation Trust (RHM), London, UK
| | - David Hawkes
- Centre for Medical Image Computing, Department of Medical Physics and Bioengineering, UCL, London, UK
| | - Isabel dos Santos Silva
- Department of Non-Communicable Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
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10
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Vavourakis V, Eiben B, Hipwell JH, Williams NR, Keshtgar M, Hawkes DJ. Multiscale Mechano-Biological Finite Element Modelling of Oncoplastic Breast Surgery-Numerical Study towards Surgical Planning and Cosmetic Outcome Prediction. PLoS One 2016; 11:e0159766. [PMID: 27466815 PMCID: PMC4965022 DOI: 10.1371/journal.pone.0159766] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 07/06/2016] [Indexed: 02/02/2023] Open
Abstract
Surgical treatment for early-stage breast carcinoma primarily necessitates breast conserving therapy (BCT), where the tumour is removed while preserving the breast shape. To date, there have been very few attempts to develop accurate and efficient computational tools that could be used in the clinical environment for pre-operative planning and oncoplastic breast surgery assessment. Moreover, from the breast cancer research perspective, there has been very little effort to model complex mechano-biological processes involved in wound healing. We address this by providing an integrated numerical framework that can simulate the therapeutic effects of BCT over the extended period of treatment and recovery. A validated, three-dimensional, multiscale finite element procedure that simulates breast tissue deformations and physiological wound healing is presented. In the proposed methodology, a partitioned, continuum-based mathematical model for tissue recovery and angiogenesis, and breast tissue deformation is considered. The effectiveness and accuracy of the proposed numerical scheme is illustrated through patient-specific representative examples. Wound repair and contraction numerical analyses of real MRI-derived breast geometries are investigated, and the final predictions of the breast shape are validated against post-operative follow-up optical surface scans from four patients. Mean (standard deviation) breast surface distance errors in millimetres of 3.1 (±3.1), 3.2 (±2.4), 2.8 (±2.7) and 4.1 (±3.3) were obtained, demonstrating the ability of the surgical simulation tool to predict, pre-operatively, the outcome of BCT to clinically useful accuracy.
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Affiliation(s)
- Vasileios Vavourakis
- Centre for Medical Image Computing, Department of Medical Physics & Biomedical Engineering, University College London, Gower Street, London, WC1E 6BT, United Kingdom
- * E-mail:
| | - Bjoern Eiben
- Centre for Medical Image Computing, Department of Medical Physics & Biomedical Engineering, University College London, Gower Street, London, WC1E 6BT, United Kingdom
| | - John H. Hipwell
- Centre for Medical Image Computing, Department of Medical Physics & Biomedical Engineering, University College London, Gower Street, London, WC1E 6BT, United Kingdom
| | - Norman R. Williams
- Division of Surgery & Interventional Science, University College London, 132 Hampstead Road, London, NW1 2BX, United Kingdom
| | - Mo Keshtgar
- Department of Surgery, Royal Free Hospital, University College London, Pond Street, London, NW3 2QG, United Kingdom
| | - David J. Hawkes
- Centre for Medical Image Computing, Department of Medical Physics & Biomedical Engineering, University College London, Gower Street, London, WC1E 6BT, United Kingdom
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11
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McCormack VA, Burton A, dos-Santos-Silva I, Hipwell JH, Dickens C, Salem D, Kamal R, Hartman M, Lee CPL, Chia KS, Ozmen V, Aribal ME, Flugelman AA, Lajous M, Lopez-Riduara R, Rice M, Romieu I, Ursin G, Qureshi S, Ma H, Lee E, van Gils CH, Wanders JOP, Vinayak S, Ndumia R, Allen S, Vinnicombe S, Moss S, Won Lee J, Kim J, Pereira A, Garmendia ML, Sirous R, Sirous M, Peplonska B, Bukowska A, Tamimi RM, Bertrand K, Nagata C, Kwong A, Vachon C, Scott C, Perez-Gomez B, Pollan M, Maskarinec G, Giles G, Hopper J, Stone J, Rajaram N, Teo SH, Mariapun S, Yaffe MJ, Schüz J, Chiarelli AM, Linton L, Boyd NF. International Consortium on Mammographic Density: Methodology and population diversity captured across 22 countries. Cancer Epidemiol 2016; 40:141-51. [PMID: 26724463 PMCID: PMC4738079 DOI: 10.1016/j.canep.2015.11.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [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: 09/02/2015] [Revised: 11/12/2015] [Accepted: 11/30/2015] [Indexed: 12/31/2022]
Abstract
Mammographic density (MD) is a quantitative trait, measurable in all women, and is among the strongest markers of breast cancer risk. The population-based epidemiology of MD has revealed genetic, lifestyle and societal/environmental determinants, but studies have largely been conducted in women with similar westernized lifestyles living in countries with high breast cancer incidence rates. To benefit from the heterogeneity in risk factors and their combinations worldwide, we created an International Consortium on Mammographic Density (ICMD) to pool individual-level epidemiological and MD data from general population studies worldwide. ICMD aims to characterize determinants of MD more precisely, and to evaluate whether they are consistent across populations worldwide. We included 11755 women, from 27 studies in 22 countries, on whom individual-level risk factor data were pooled and original mammographic images were re-read for ICMD to obtain standardized comparable MD data. In the present article, we present (i) the rationale for this consortium; (ii) characteristics of the studies and women included; and (iii) study methodology to obtain comparable MD data from original re-read films. We also highlight the risk factor heterogeneity captured by such an effort and, thus, the unique insight the pooled study promises to offer through wider exposure ranges, different confounding structures and enhanced power for sub-group analyses.
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Affiliation(s)
- Valerie A McCormack
- Section of Environment and Radiation, International Agency for Research on Cancer, Lyon, France.
| | - Anya Burton
- Section of Environment and Radiation, International Agency for Research on Cancer, Lyon, France
| | - Isabel dos-Santos-Silva
- Dept of Non-Communicable Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
| | - John H Hipwell
- Centre for Medical Image Computing, University College London, UK
| | | | | | - Rasha Kamal
- Woman Imaging Unit, Radiodiagnosis Department, Kasr El Aini, Cairo University Hospitals, Cairo, Egypt
| | - Mikael Hartman
- Department of Surgery, Yong Loo Lin School of Medicine and Saw Swee Hock School of Public Health, National University of Singapore, Singapore
| | - Charmaine Pei Ling Lee
- Department of Surgery, Yong Loo Lin School of Medicine and Saw Swee Hock School of Public Health, National University of Singapore, Singapore; NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore
| | - Kee-Seng Chia
- NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore
| | | | | | | | - Martín Lajous
- Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Boston, USA; Center for Research on Population Health, Instituto Nacional de Salud Pública, Mexico, Mexico City, Mexico
| | - Ruy Lopez-Riduara
- Center for Research on Population Health, Instituto Nacional de Salud Pública, Mexico, Mexico City, Mexico
| | - Megan Rice
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, USA
| | - Isabelle Romieu
- Section of Nutrition and Metabolism, International Agency for Research on Cancer, Lyon, France
| | - Giske Ursin
- Cancer Registry of Norway, Oslo, Norway; Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway; Department of Preventive Medicine, University of Southern California, Los Angeles, California, USA
| | - Samera Qureshi
- Norwegian Center for Minority Health Research (NAKMI), Oslo, Norway
| | - Huiyan Ma
- Department of Population Sciences, Beckman Research Institute, City of Hope, Duarte, USA
| | - Eunjung Lee
- Department of Preventive Medicine, University of Southern California, Los Angeles, California, USA
| | - Carla H van Gils
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, The Netherlands
| | - Johanna O P Wanders
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, The Netherlands
| | | | - Rose Ndumia
- Aga Khan University Hospital, Nairobi, Kenya
| | - Steve Allen
- Department of Imaging, Royal Marsden NHS Foundation Trust, London, UK
| | - Sarah Vinnicombe
- Division of Cancer Research, Ninewells Hospital & Medical School, Dundee, UK
| | - Sue Moss
- Wolfson Institute of Preventive Medicine, Queen Mary University of London, UK
| | | | - Jisun Kim
- Asan Medical Center, Seoul, Republic of Korea
| | - Ana Pereira
- Institute of Nutrition and Food Technology, University of Chile, Chile
| | | | - Reza Sirous
- Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mehri Sirous
- Isfahan University of Medical Sciences, Isfahan, Iran
| | | | | | - Rulla M Tamimi
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, USA
| | | | | | - Ava Kwong
- Division of Breast Surgery, The University of Hong Kong Faculty of Medicine, and Department of Surgery, Hong Kong Sanatorium and Hospital, Hong Kong, People's Republic of China
| | - Celine Vachon
- Dept Health Sciences Research, Mayo Clinic, Rochester, Minnesota, USA
| | - Christopher Scott
- Dept Health Sciences Research, Mayo Clinic, Rochester, Minnesota, USA
| | - Beatriz Perez-Gomez
- Cancer Epidemiology Unit, Instituto de Salud Carlos III and CIBERESP, Madrid, Spain
| | - Marina Pollan
- Cancer Epidemiology Unit, Instituto de Salud Carlos III and CIBERESP, Madrid, Spain
| | | | - Graham Giles
- Cancer Epidemiology Centre, Cancer Council Victoria, Melbourne, Australia; School of Population and Global Health, The University of Melbourne, Australia
| | - John Hopper
- School of Population and Global Health, The University of Melbourne, Australia
| | - Jennifer Stone
- Centre for Genetic Origins of Health and Disease, University of Western Australia, Australia
| | - Nadia Rajaram
- Breast Cancer Research Group, University Malaya Medical Centre, University Malaya, Kuala Lumpur, Malaysia
| | - Soo-Hwang Teo
- Breast Cancer Research Group, University Malaya Medical Centre, University Malaya, Kuala Lumpur, Malaysia; Cancer Research Malaysia, Subang Jaya, Malaysia
| | - Shivaani Mariapun
- Breast Cancer Research Group, University Malaya Medical Centre, University Malaya, Kuala Lumpur, Malaysia
| | | | - Joachim Schüz
- Section of Environment and Radiation, International Agency for Research on Cancer, Lyon, France
| | - Anna M Chiarelli
- Ontario Breast Screening Program, Cancer Care Ontario, Toronto, Canada
| | - Linda Linton
- Princess Margaret Cancer Centre, Toronto, Canada
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12
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Lacher RM, Hipwell JH, Williams NR, Keshtgar MRS, Hawkes DJ, Stoyanov D. Low-cost surface reconstruction for aesthetic results assessment and prediction in breast cancer surgery. Annu Int Conf IEEE Eng Med Biol Soc 2016; 2015:5871-4. [PMID: 26737627 DOI: 10.1109/embc.2015.7319727] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The high incidence and low mortality of breast cancer surgery has led to an increasing emphasis on the cosmetic outcome of surgical treatment. Advances in aesthetic evaluation, as well as surgical planning and outcome prediction, have been investigated by using geometrically precise 3D modelling of the breast surface prior to surgery and after the procedure. However, existing solutions are based on expensive site specific setups and remain weakly validated. In this paper, we explore the possibility of using low-cost RGBD cameras as an affordable and mobile system for breast surface reconstruction. The methodology relies on sensor calibration, uncertainty-driven point filtering, dense reconstruction and subsequent multi-view joint optimization to diffuse residual pose errors. Results from a phantom study, with ground truth obtained through commercially available scanners, indicate that the approach is promising with RMS errors in order of 2 mm. A clinical study shows the practical applicability of our method and compares favourably to high-end scanning solutions.
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13
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Abstract
Breast radiology encompasses the full range of imaging modalities from routine imaging via x-ray mammography, magnetic resonance imaging and ultrasound (both two- and three-dimensional), to more recent technologies such as digital breast tomosynthesis, and dedicated breast imaging systems for positron emission mammography and ultrasound tomography. In addition new and experimental modalities, such as Photoacoustics, Near Infrared Spectroscopy and Electrical Impedance Tomography etc, are emerging. The breast is a highly deformable structure however, and this greatly complicates visual comparison of imaging modalities for the purposes of breast screening, cancer diagnosis (including image guided biopsy), tumour staging, treatment monitoring, surgical planning and simulation of the effects of surgery and wound healing etc. Due primarily to the challenges posed by these gross, non-rigid deformations, development of automated methods which enable registration, and hence fusion, of information within and across breast imaging modalities, and between the images and the physical space of the breast during interventions, remains an active research field which has yet to translate suitable methods into clinical practice. This review describes current research in the field of breast biomechanical modelling and identifies relevant publications where the resulting models have been incorporated into breast image registration and simulation algorithms. Despite these developments there remain a number of issues that limit clinical application of biomechanical modelling. These include the accuracy of constitutive modelling, implementation of representative boundary conditions, failure to meet clinically acceptable levels of computational cost, challenges associated with automating patient-specific model generation (i.e. robust image segmentation and mesh generation) and the complexity of applying biomechanical modelling methods in routine clinical practice.
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Affiliation(s)
- John H Hipwell
- Centre for Medical Image Computing, Malet Place Engineering Building, University College London, Gower Street, London WC1E 6BT, UK
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14
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Eiben B, Vavourakis V, Hipwell JH, Kabus S, Buelow T, Lorenz C, Mertzanidou T, Reis S, Williams NR, Keshtgar M, Hawkes DJ. Symmetric Biomechanically Guided Prone-to-Supine Breast Image Registration. Ann Biomed Eng 2015; 44:154-73. [PMID: 26577254 PMCID: PMC4690842 DOI: 10.1007/s10439-015-1496-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [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: 03/31/2015] [Accepted: 10/23/2015] [Indexed: 10/27/2022]
Abstract
Prone-to-supine breast image registration has potential application in the fields of surgical and radiotherapy planning, image guided interventions, and multi-modal cancer diagnosis, staging, and therapy response prediction. However, breast image registration of three dimensional images acquired in different patient positions is a challenging problem, due to large deformations induced to the soft breast tissue caused by the change in gravity loading. We present a symmetric, biomechanical simulation based registration framework which aligns the images in a central, virtually unloaded configuration. The breast tissue is modelled as a neo-Hookean material and gravity is considered as the main source of deformation in the original images. In addition to gravity, our framework successively applies image derived forces directly into the unloading simulation in place of a subsequent image registration step. This results in a biomechanically constrained deformation. Using a finite difference scheme avoids an explicit meshing step and enables simulations to be performed directly in the image space. The explicit time integration scheme allows the motion at the interface between chest and breast to be constrained along the chest wall. The feasibility and accuracy of the approach presented here was assessed by measuring the target registration error (TRE) using a numerical phantom with known ground truth deformations, nine clinical prone MRI and supine CT image pairs, one clinical prone-supine CT image pair and four prone-supine MRI image pairs. The registration reduced the mean TRE for the numerical phantom experiment from initially 19.3 to 0.9 mm and the combined mean TRE for all fourteen clinical data sets from 69.7 to 5.6 mm.
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Affiliation(s)
- Björn Eiben
- Department of Medical Physics & Biomedical Engineering, Centre for Medical Image Computing, University College London, Gower Street, London, WC1E 6BT, UK.
| | - Vasileios Vavourakis
- Department of Medical Physics & Biomedical Engineering, Centre for Medical Image Computing, University College London, Gower Street, London, WC1E 6BT, UK
| | - John H Hipwell
- Department of Medical Physics & Biomedical Engineering, Centre for Medical Image Computing, University College London, Gower Street, London, WC1E 6BT, UK
| | - Sven Kabus
- Philips GmbH Innovative Technologies, Research Laboratories Hamburg, Röntgenstrasse 24-26, 22335, Hamburg, Germany
| | - Thomas Buelow
- Philips GmbH Innovative Technologies, Research Laboratories Hamburg, Röntgenstrasse 24-26, 22335, Hamburg, Germany
| | - Cristian Lorenz
- Philips GmbH Innovative Technologies, Research Laboratories Hamburg, Röntgenstrasse 24-26, 22335, Hamburg, Germany
| | - Thomy Mertzanidou
- Department of Medical Physics & Biomedical Engineering, Centre for Medical Image Computing, University College London, Gower Street, London, WC1E 6BT, UK
| | - Sara Reis
- Department of Medical Physics & Biomedical Engineering, Centre for Medical Image Computing, University College London, Gower Street, London, WC1E 6BT, UK
| | - Norman R Williams
- Clinical Trials Group, Division of Surgery, University College London, Gower Street, London, WC1E 6BT, UK
| | - Mohammed Keshtgar
- Department of Surgery, Royal Free Hospital, Pond Street, London, NW3 2QG, UK.,Division of Surgery, University College London, Gower Street, London, WC1E 6BT, UK
| | - David J Hawkes
- Department of Medical Physics & Biomedical Engineering, Centre for Medical Image Computing, University College London, Gower Street, London, WC1E 6BT, UK
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15
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Wijeratne PA, Vavourakis V, Hipwell JH, Voutouri C, Papageorgis P, Stylianopoulos T, Evans A, Hawkes DJ. Multiscale modelling of solid tumour growth: the effect of collagen micromechanics. Biomech Model Mechanobiol 2015; 15:1079-90. [PMID: 26564173 DOI: 10.1007/s10237-015-0745-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [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: 07/12/2015] [Accepted: 11/02/2015] [Indexed: 01/16/2023]
Abstract
Here we introduce a model of solid tumour growth coupled with a multiscale biomechanical description of the tumour microenvironment, which facilitates the explicit simulation of fibre-fibre and tumour-fibre interactions. We hypothesise that such a model, which provides a purely mechanical description of tumour-host interactions, can be used to explain experimental observations of the effect of collagen micromechanics on solid tumour growth. The model was specified to mouse tumour data, and numerical simulations were performed. The multiscale model produced lower stresses than an equivalent continuum-like approach, due to a more realistic remodelling of the collagen microstructure. Furthermore, solid tumour growth was found to cause a passive mechanical realignment of fibres at the tumour boundary from a random to a circumferential orientation. This is in accordance with experimental observations, thus demonstrating that such a response can be explained as purely mechanical. Finally, peritumoural fibre network anisotropy was found to produce anisotropic tumour morphology. The dependency of tumour morphology on the peritumoural microstructure was reduced by adding a load-bearing non-collagenous component to the fibre network constitutive equation.
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Affiliation(s)
- Peter A Wijeratne
- Department of Medical Physics and Bioengineering, Centre for Medical Image Computing, University College London, Engineering Front Building, Malet Place, London, WC1E 6BT, UK.
| | - Vasileios Vavourakis
- Department of Medical Physics and Bioengineering, Centre for Medical Image Computing, University College London, Engineering Front Building, Malet Place, London, WC1E 6BT, UK
| | - John H Hipwell
- Department of Medical Physics and Bioengineering, Centre for Medical Image Computing, University College London, Engineering Front Building, Malet Place, London, WC1E 6BT, UK
| | - Chrysovalantis Voutouri
- Cancer Biophysics Laboratory, Department of Mechanical and Manufacturing Engineering, University of Cyprus, 1678, Nicosia, Cyprus
| | - Panagiotis Papageorgis
- Cancer Biophysics Laboratory, Department of Mechanical and Manufacturing Engineering, University of Cyprus, 1678, Nicosia, Cyprus
| | - Triantafyllos Stylianopoulos
- Cancer Biophysics Laboratory, Department of Mechanical and Manufacturing Engineering, University of Cyprus, 1678, Nicosia, Cyprus
| | | | - David J Hawkes
- Department of Medical Physics and Bioengineering, Centre for Medical Image Computing, University College London, Engineering Front Building, Malet Place, London, WC1E 6BT, UK
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Han L, Hipwell JH, Eiben B, Barratt D, Modat M, Ourselin S, Hawkes DJ. A nonlinear biomechanical model based registration method for aligning prone and supine MR breast images. IEEE Trans Med Imaging 2014; 33:682-694. [PMID: 24595342 DOI: 10.1109/tmi.2013.2294539] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Preoperative diagnostic magnetic resonance (MR) breast images can provide good contrast between different tissues and 3-D information about suspicious tissues. Aligning preoperative diagnostic MR images with a patient in the theatre during breast conserving surgery could assist surgeons in achieving the complete excision of cancer with sufficient margins. Typically, preoperative diagnostic MR breast images of a patient are obtained in the prone position, while surgery is performed in the supine position. The significant shape change of breasts between these two positions due to gravity loading, external forces and related constraints makes the alignment task extremely difficult. Our previous studies have shown that either nonrigid intensity-based image registration or biomechanical modelling alone are limited in their ability to capture such a large deformation. To tackle this problem, we proposed in this paper a nonlinear biomechanical model-based image registration method with a simultaneous optimization procedure for both the material parameters of breast tissues and the direction of the gravitational force. First, finite element (FE) based biomechanical modelling is used to estimate a physically plausible deformation of the pectoral muscle and the major deformation of breast tissues due to gravity loading. Then, nonrigid intensity-based image registration is employed to recover the remaining deformation that FE analyses do not capture due to the simplifications and approximations of biomechanical models and the uncertainties of external forces and constraints. We assess the registration performance of the proposed method using the target registration error of skin fiducial markers and the Dice similarity coefficient (DSC) of fibroglandular tissues. The registration results on prone and supine MR image pairs are compared with those from two alternative nonrigid registration methods for five breasts. Overall, the proposed algorithm achieved the best registration performance on fiducial markers (target registration error, 8.44 ±5.5 mm for 45 fiducial markers) and higher overlap rates on segmentation propagation of fibroglandular tissues (DSC value > 82%).
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Han L, Hipwell JH, Tanner C, Taylor Z, Mertzanidou T, Cardoso J, Ourselin S, Hawkes DJ. Development of patient-specific biomechanical models for predicting large breast deformation. Phys Med Biol 2011; 57:455-72. [DOI: 10.1088/0031-9155/57/2/455] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Pinto Pereira SM, McCormack VA, Hipwell JH, Record C, Wilkinson LS, Moss SM, Hawkes DJ, dos-Santos-Silva I. Localized fibroglandular tissue as a predictor of future tumor location within the breast. Cancer Epidemiol Biomarkers Prev 2011; 20:1718-25. [PMID: 21693627 DOI: 10.1158/1055-9965.epi-11-0423] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND Mammographic density (MD) is a strong marker of breast cancer risk, but it is unclear whether tumors arise specifically within dense tissue. METHODS In 231 British women diagnosed with breast cancer after at least one negative annual screening during a mammographic screening trial, we assessed whether tumor location was related to localized MD 5 years prior to diagnosis. Radiologists identified tumor locations on digitised films. We used a validated algorithm to align serial images from the same woman to locate the corresponding point on the prediagnostic film. A virtual 1 cm square grid was overlaid on prediagnostic films and MD calculated for each square within a woman's breast (mean = 271 squares/film). Conditional logistic regression, matching on a woman's breast, was used to estimate the odds of a tumor arising in a square in relation to its prediagnostic square-specific MD. RESULTS Median (interquartile range) prediagnostic MD was 98.2% (46.8%-100%) in 1 cm-squares that subsequently contained the tumor and 41.0% (31.5%-53.9%) for the whole breast. The odds of a tumor arising in a 1 cm-square were, respectively, 6.1 (95% CI: 1.9-20.1), 16.6 (5.2-53.2), and 25.5-fold (8.1-80.3) higher for squares in the second, third, and fourth quartiles of prediagnostic MD relative to those in the lowest quartile within that breast (P(trend) < 0.001). The corresponding odds ratios were 2.3 (1.3-4.0), 3.9 (2.3-6.4), and 4.6 (2.8-7.6) if a 3 cm-square grid was used. CONCLUSION Tumors arise predominantly within the radiodense breast tissue. IMPACT Localized MD may be used as a predictor of subsequent tumor location within the breast.
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Affiliation(s)
- Snehal M Pinto Pereira
- Department of Non-Communicable Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
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Pinto Pereira SM, Hipwell JH, McCormack VA, Tanner C, Moss SM, Wilkinson LS, Khoo LAL, Pagliari C, Skippage PL, Kliger CJ, Hawkes DJ, dos Santos Silva IM. Automated registration of diagnostic to prediagnostic x-ray mammograms: Evaluation and comparison to radiologists’ accuracy. Med Phys 2010; 37:4530-9. [DOI: 10.1118/1.3457470] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [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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Hipwell JH, Tanner C, Crum WR, Schnabel JA, Hawkes DJ. A new validation method for X-ray mammogram registration algorithms using a projection model of breast X-ray compression. IEEE Trans Med Imaging 2007; 26:1190-200. [PMID: 17896592 DOI: 10.1109/tmi.2007.903569] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Establishing spatial correspondence between features visible in X-ray mammograms obtained at different times has great potential to aid assessment and quantitation of change in the breast indicative of malignancy. The literature contains numerous nonrigid registration algorithms developed for this purpose, but existing approaches are flawed by the assumption of inappropriate 2-D transformation models and quantitative estimation of registration accuracy is limited. In this paper, we describe a novel validation method which simulates plausible mammographic compressions of the breast using a magnetic resonance imaging (MRI) derived finite element model. By projecting the resulting known 3-D displacements into 2-D and generating pseudo-mammograms from these same compressed magnetic resonance (MR) volumes, we can generate convincing images with known 2-D displacements with which to validate a registration algorithm. We illustrate this approach by computing the accuracy for two conventional nonrigid 2-D registration algorithms applied to mammographic test images generated from three patient MR datasets. We show that the accuracy of these algorithms is close to the best achievable using a 2-D one-to-one correspondence model but that new algorithms incorporating more representative transformation models are required to achieve sufficiently accurate registrations for this application.
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Affiliation(s)
- John H Hipwell
- University College London, Centre for Medical Image Computing, London, WC1E 6BT U.K.
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Penney GP, Edwards PJ, Hipwell JH, Slomczykowski M, Revie I, Hawkes DJ. Postoperative Calculation of Acetabular Cup Position Using 2-D–3-D Registration. IEEE Trans Biomed Eng 2007; 54:1342-8. [PMID: 17605366 DOI: 10.1109/tbme.2007.890737] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
A method to accurately measure the position and orientation of an acetabular cup implant from postoperative X-rays has been designed and validated. The method uses 2-D-3-D registration to align both the prosthesis and the preoperative computed tomography (CT) volume to the X-ray image. This allows the position of the implant to be calculated with respect to a CT-based surgical plan. Experiments have been carried out using ten sets of patient data. A conventional plain-film measurement technique was also investigated. A gold standard implant position and orientation was calculated using postoperative CT. Results show our method to be significantly more accurate than the plain-film method for calculating cup anteversion. Cup orientation and position could be measured to within a mean absolute error of 1.4 mm or degrees.
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Affiliation(s)
- Graeme P Penney
- Imaging Sciences Division, Guy's King's and St Thomas' Schools of Medicine, Kings College London, London SEI 3RB, UK.
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Hipwell JH, Penney GP, McLaughlin RA, Rhode K, Summers P, Cox TC, Byrne JV, Noble JA, Hawkes DJ. Intensity-based 2-D-3-D registration of cerebral angiograms. IEEE Trans Med Imaging 2003; 22:1417-1426. [PMID: 14606675 DOI: 10.1109/tmi.2003.819283] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We propose a new method for aligning three-dimensional (3-D) magnetic resonance angiography (MRA) with 2-D X-ray digital subtraction angiograms (DSA). Our method is developed from our algorithm to register computed tomography volumes to X-ray images based on intensity matching of digitally reconstructed radiographs (DRRs). To make the DSA and DRR more similar, we transform the MRA images to images of the vasculature and set to zero the contralateral side of the MRA to that imaged with DSA. We initialize the search for a match on a user defined circular region of interest. We have tested six similarity measures using both unsegmented MRA and three segmentation variants of the MRA. Registrations were carried out on images of a physical neuro-vascular phantom and images obtained during four neuro-vascular interventions. The most accurate and robust registrations were obtained using the pattern intensity, gradient difference, and gradient correlation similarity measures, when used in conjunction with the most sophisticated MRA segmentations. Using these measures, 95% of the phantom start positions and 82% of the clinical start positions were successfully registered. The lowest root mean square reprojection errors were 1.3 mm (standard deviation 0.6) for the phantom and 1.5 mm (standard deviation 0.9) for the clinical data sets. Finally, we present a novel method for the comparison of similarity measure performance using a technique borrowed from receiver operator characteristic analysis.
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Affiliation(s)
- John H Hipwell
- Division of Imaging Sciences, UMDS, Guy's & St Thomas' Hospitals, London SE1 9RT, UK.
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Olson JA, Strachan FM, Hipwell JH, Goatman KA, McHardy KC, Forrester JV, Sharp PF. A comparative evaluation of digital imaging, retinal photography and optometrist examination in screening for diabetic retinopathy. Diabet Med 2003; 20:528-34. [PMID: 12823232 DOI: 10.1046/j.1464-5491.2003.00969.x] [Citation(s) in RCA: 104] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIMS To compare the respective performances of digital retinal imaging, fundus photography and slit-lamp biomicroscopy performed by trained optometrists, in screening for diabetic retinopathy. To assess the potential contribution of automated digital image analysis to a screening programme. METHODS A group of 586 patients recruited from a diabetic clinic underwent three or four mydriatic screening methods for retinal examination. The respective performances of digital imaging (n=586; graded manually), colour slides (n=586; graded manually), and slit-lamp examination by specially trained optometrists (n=485), were evaluated against a reference standard of slit-lamp biomicroscopy by ophthalmologists with a special interest in medical retina. The performance of automated grading of the digital images by computer was also assessed. RESULTS Slit-lamp examination by optometrists for referable diabetic retinopathy achieved a sensitivity of 73% (52-88) and a specificity of 90% (87-93). Using two-field imaging, manual grading of red-free digital images achieved a sensitivity of 93% (82-98) and a specificity of 87% (84-90), and for colour slides, a sensitivity of 96% (87-100) and a specificity of 89% (86-91). Almost identical results were achieved for both methods with single macular field imaging. Digital imaging had a lower technical failure rate (4.4% of patients) than colour slide photography (11.9%). Applying an automated grading protocol to the digital images detected any retinopathy, with a sensitivity of 83% (77-89) and a specificity of 71% (66-75) and diabetic macular oedema with a sensitivity of 76% (53-92) and a specificity of 85% (82-88). CONCLUSIONS Both manual grading methods produced similar results whether using a one- or two-field protocol. Technical failures rates, and hence need for recall, were lower with digital imaging. One-field grading of fundus photographs appeared to be as effective as two-field. The optometrists achieved the lowest sensitivities but reported no technical failures. Automated grading of retinal images can improve efficiency of resource utilization in diabetic retinopathy screening.
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Affiliation(s)
- J A Olson
- Department of Ophthalmology, The Eye Clinic, Aberdeen Royal Infirmary, Grampian University Hospitals NHS Trust, Aberdeen, UK.
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Hipwell JH, Strachan F, Olson JA, McHardy KC, Sharp PF, Forrester JV. Automated detection of microaneurysms in digital red-free photographs: a diabetic retinopathy screening tool. Diabet Med 2000; 17:588-94. [PMID: 11073180 DOI: 10.1046/j.1464-5491.2000.00338.x] [Citation(s) in RCA: 114] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIMS To develop a technique to detect microaneurysms automatically in 50 degrees digital red-free fundus photographs and evaluate its performance as a tool for screening diabetic patients for retinopathy. METHODS Candidate microaneurysms are extracted, after the image has been modified to remove variations in background intensity, by algorithms that enhance small round features. Each microaneurysm candidate is then classified according to its intensity and size by the application of a set of rules derived from a training set of 102 images. RESULTS When 3,783 individual images were analysed and the results compared with the opinion of a clinical research fellow examining the same images, the program achieved a sensitivity of 81% and a specificity of 93% for the detection of images containing microaneurysms. Nine hundred and twenty-five sets of 4 images per patient were then analysed and the total number of microaneurysms detected compared with the overall patient retinopathy grade derived by the clinician examining the same images. In this context, intended to mimic a screening situation, the program achieved a sensitivity of 85% and a specificity of 76% for the detection of patients with (any) retinopathy (positive predictive value 0.71, negative predictive value 0.88). CONCLUSIONS An automated technique was developed to detect retinopathy in digital red-free fundus images that can form part of a diabetic retinopathy screening programme. It is believed that it can perform a useful role in this context identifying images worthy of closer inspection or eliminating 50% or more of the screening population who have no retinopathy.
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Affiliation(s)
- J H Hipwell
- Bio-medical Physics and Bio-engineering University of Aberdeen, Foresterhill, UK.
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Affiliation(s)
- P F Sharp
- Department of Biomedical Physics and Bioengineering, University of Aberdeen
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Hipwell JH, Manivannan A, Vieira P, Sharp PF, Forrester JV. Quantifying changes in retinal circulation: the generation of parametric images from fluorescein angiograms. Physiol Meas 1998; 19:165-80. [PMID: 9626681 DOI: 10.1088/0967-3334/19/2/004] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Fluorescein angiography is an established technique for examining the functional integrity of the retinal circulation. The ability to quantify this function offers the possibility of early detection of changes due to retinopathy. We have developed a technique to generate functional, parametric images of the retinal circulation. A given angiogram is first registered to align consecutive frames. At each point in the retina, a graph of fluorescein intensity versus time is then constructed and fitted with a gamma variate curve. Parameters are extracted from these curves and formed into parametric images showing the variation in fluorescein passage across the entire area of the angiogram. Parameters examined to date include time to maximum intensity, time of arrival and rise time. The technique has been demonstrated using photographic and scanning laser ophthalmoscopic angiograms of both normal subjects and patients with a variety of retinopathies. The time to maximum images of the normal subjects reveals a similar fillings pattern in each case, whilst the pathologies present in the abnormal angiograms are clearly identified. The generation of functional time to maximum images enables the health of the retinal circulation to be quantified with respect to the rate at which the vasculature fills with fluorescein. This offers a potential tool for detecting the onset of retinopathy and monitoring its progression.
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Affiliation(s)
- J H Hipwell
- Department of Bio-Medical Physics and Bio-Engineering, University of Aberdeen, UK
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