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You searched for subject:(CDMAM Phantom). Showing records 1 – 3 of 3 total matches.

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1. Sousa, Maria Angélica Zucareli. Avaliação automática da qualidade de imagens mamográficas digitais geradas com simulador CDMAM.

Degree: Mestrado, Processamento de Sinais de Instrumentação, 2013, University of São Paulo

Os requisitos técnicos da qualidade da imagem em mamografia estabelecidos por normas nacionais e internacionais incluem parâmetros de qualidade que podem ser avaliados através da realização de testes periódicos. Estes parâmetros podem ser medidos com a aquisição e leitura de imagens de objetos (phantoms) que simulam as estruturas presentes em uma mamografia. O phantom CDMAM foi confeccionado especificamente para a realização de testes que utilizam um procedimento padrão para se determinar um limiar de contraste para cada diâmetro de disco presentes em suas imagens. No entanto, esta tarefa é bastante trabalhosa e consome tempo, além de estar sujeita a uma significativa dependência do observador, diminuindo a precisão das aferições. Nesse sentido, o propósito deste trabalho é o desenvolvimento de um software que auxilie o profissional na realização dos testes, reduzindo a subjetividade devida aos observadores e correlacionando as leituras automatizadas com o sistema visual humano, sem a necessidade de se efetuar a correção dos resultados, como é realizado em diversos trabalhos encontrados na literatura. Para isso, foram utilizadas imagens obtidas por cinco sistemas CR e um método de detecção baseado na confecção de filtros circulares correlatores. A correlação com a visão humana fundamentou-se nos parâmetros de Weber, que descrevem o comportamento do sistema visual na discriminação do contraste em imagens digitais. A classificação dos discos contidos na imagem do phantom entre visível ou não visível foi efetuada a partir de uma ferramenta de mineração de dados conhecida como WEKA (Waikato Environment for Knowledge Analysis) associada ao algoritmo J48, que promove a construção de modelos de árvore de decisão. O resultado da implementação destas árvores de decisão foi a obtenção de um sistema de auxílio ao especialista que reforça a sua integridade na avaliação a partir de resultados estáveis e de fácil interpretação, atingindo acurácias de até 95%.

Technical requirements of image quality in mammography established by national and international norms include quality parameters which can be achieved by conducting periodic tests. It is recommended that some quality parameters are measured from images acquired by exposing specific phantoms, as CDMAM, in such systems. Nevertheless, this task is hard-working and time consuming, besides to be subject to a significant dependence of the observer, reducing the measurements accuracy. Accordingly, the purpose of this work is the development of a software to assist in the professional testing, reducing the subjectivity due to the observers and correlating the automated readings with the human visual system, without the need to make the correction of the results, as is done in many studies in the literature. For this, we used 57 images obtained for five CR systems and a method of detection based on circular correlators filters. The correlation with human vision was based on the Weber\'s parameters which describe the behavior of the visual system to discriminate the contrast in…

Advisors/Committee Members: Schiabel, Homero.

Subjects/Keywords: Controle de qualidade em mamografia; Digital mammography; Human visual perception; Mamografia digital; Percepção visual humana; Phantom CDMAM; Phantom CDMAM; Quality control in mammography

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Sousa, M. A. Z. (2013). Avaliação automática da qualidade de imagens mamográficas digitais geradas com simulador CDMAM. (Masters Thesis). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/18/18152/tde-27082013-084937/ ;

Chicago Manual of Style (16th Edition):

Sousa, Maria Angélica Zucareli. “Avaliação automática da qualidade de imagens mamográficas digitais geradas com simulador CDMAM.” 2013. Masters Thesis, University of São Paulo. Accessed December 13, 2019. http://www.teses.usp.br/teses/disponiveis/18/18152/tde-27082013-084937/ ;.

MLA Handbook (7th Edition):

Sousa, Maria Angélica Zucareli. “Avaliação automática da qualidade de imagens mamográficas digitais geradas com simulador CDMAM.” 2013. Web. 13 Dec 2019.

Vancouver:

Sousa MAZ. Avaliação automática da qualidade de imagens mamográficas digitais geradas com simulador CDMAM. [Internet] [Masters thesis]. University of São Paulo; 2013. [cited 2019 Dec 13]. Available from: http://www.teses.usp.br/teses/disponiveis/18/18152/tde-27082013-084937/ ;.

Council of Science Editors:

Sousa MAZ. Avaliação automática da qualidade de imagens mamográficas digitais geradas com simulador CDMAM. [Masters Thesis]. University of São Paulo; 2013. Available from: http://www.teses.usp.br/teses/disponiveis/18/18152/tde-27082013-084937/ ;


Freie Universität Berlin

2. Miller, Jessica Barbara. Lossy JPEG 2000 compression in digital mammography evaluation of image quality, radiation dose and breast density using 600 mammograms of the CDMAM phantom.

Degree: 2011, Freie Universität Berlin

The DICOM standard supports both quantitative and qualitative lossy compression of mammograms. The purpose of this study was to investigate qualitative JPEG 2000 lossy compression and how different factors such as breast density, radiation dose, and lossy compression levels affect image quality. Material and Methods: The CDMAM phantom Artinis 3.4 was radiographed with 4 different object thicknesses and 5 different doses. The images were compressed at 10 different quality compression levels resulting in 600 images, image quality was assessed by the software interpolated IQFinv-value. Results: Lossy 90 resulted in 89% data reduction, lossy 70 in 95% and lossy 60 in 96%. At higher compression levels (lossy 30) resulting image quality ranged from 80% to 36%, at low compression levels (lossy 90) from 89% to 93%. Object thickness was found to significantly interact with the compression level with regard to the resulting image quality: higher object thickness resulted in increasingly poorer image quality at increasing compression levels (p < 0.05). Conclusion: Higher qualitative JPEG 2000 compression levels contribute only little additional data reduction, while the resulting image quality is exponentially worsening. Factors affecting image quality such as radiation quality and object density should be taken into account, while performing image compression. Dense objects such as CDMAM-mammogram simulating dense breasts should be compressed with caution because the image quality is already low without any compression compared to less dense mammomograms. The mammogram of a dense breast will lose even more image quality when intelligent data compression algorithms are used. Therefore a general recommendation for lossy data compression in digital mammography without an accepted threshold for image quality can´t be given. Advisors/Committee Members: [email protected] (contact), w (gender), PD Dr. med. F. Diekmann (firstReferee), PD Dr. med K. Ludwig (furtherReferee), Prof. Dr. med. V. Barth (furtherReferee).

Subjects/Keywords: Mammography; Image quality; breast density; Lossy Data Compression; JPEG 2000; CDMAM-Phantom; 600 Technik, Medizin, angewandte Wissenschaften::610 Medizin und Gesundheit

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Miller, J. B. (2011). Lossy JPEG 2000 compression in digital mammography evaluation of image quality, radiation dose and breast density using 600 mammograms of the CDMAM phantom. (Thesis). Freie Universität Berlin. Retrieved from http://dx.doi.org/10.17169/refubium-13359

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Miller, Jessica Barbara. “Lossy JPEG 2000 compression in digital mammography evaluation of image quality, radiation dose and breast density using 600 mammograms of the CDMAM phantom.” 2011. Thesis, Freie Universität Berlin. Accessed December 13, 2019. http://dx.doi.org/10.17169/refubium-13359.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Miller, Jessica Barbara. “Lossy JPEG 2000 compression in digital mammography evaluation of image quality, radiation dose and breast density using 600 mammograms of the CDMAM phantom.” 2011. Web. 13 Dec 2019.

Vancouver:

Miller JB. Lossy JPEG 2000 compression in digital mammography evaluation of image quality, radiation dose and breast density using 600 mammograms of the CDMAM phantom. [Internet] [Thesis]. Freie Universität Berlin; 2011. [cited 2019 Dec 13]. Available from: http://dx.doi.org/10.17169/refubium-13359.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Miller JB. Lossy JPEG 2000 compression in digital mammography evaluation of image quality, radiation dose and breast density using 600 mammograms of the CDMAM phantom. [Thesis]. Freie Universität Berlin; 2011. Available from: http://dx.doi.org/10.17169/refubium-13359

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation


Université Paris-Sud – Paris XI

3. Dromain, Clarisse. Optimisation de l’angiomammographie et de l’angiotomosynthèse double-énergie : Optimization of contrast enhanced digital mammography and contrast enhanced digital breast tomosynthesis.

Degree: Docteur es, Physique, 2015, Université Paris-Sud – Paris XI

Objectifs : L’objectif a été de d’optimiser les protocoles d’acquisition des examens d’angiomammographie double-énergie, d’étudier la faisabilité de l’angiotomosynthèse pour la détection et la caractérisation des tumeurs mammaires, et d’étudier la faisabilité des biopsies stéréotaxiques sous guidage de l’angiomammographie. Méthodes : Une étude d’optimisation des paramètres d’acquisition de l’angiomammographie a été réalisée dans 4 situations cliniques pour lesquelles la qualité diagnostique requise des images de basse énergie et la dose totale délivrée à la patiente ne sont pas identiques. L’optimisation des paramètres d'exposition (anode/filtre, kVp, mAs) des images de basse énergie (BE) et haute énergie (HE) a été réalisée à partir d’une modélisation théorique de la chaîne d’acquisition. Une validation a été effectuée par mesures expérimentales sur des images de fantôme d’inserts d’iode. Nous avons ensuite étudié la technique d’angiotomosynthèse mammaire basée sur une approche double-énergie. Un nouveau fantôme anthropomorphique numérique du sein et de ses lésions, basé sur l’utilisation de primitives géométriques complexes et d’une technique de maillage surfacique, a été amélioré et utilisé pour évaluer les performances de l’angiomammographie optimisée, puis de l’angiotomosynthèse en comparaison à l’angiomammographie. Enfin, nous avons proposé un scénario pour la réalisation d’un examen de stéréotaxie avec injection d’un agent de contraste iodé et étudié la faisabilité de recombinaison d’image de haute et de basse énergie acquises à des temps différents de l’injection.Résultats et conclusion : Les optima des paramètres d’exposition trouvés par simulation avec les valeurs de SDNRpixel et SDNR2pixel /Dosetotale qui en résultent, ont été confirmés expérimentalement. Les valeurs de SDNR par pixel dans les images recombinées sont augmentées pour toutes les indications cliniques en comparaison à celle obtenues avec SenoBright ® (produit commercial de référence). L'impact sur la qualité de l’image de BE, évalué par des expérimentations sur fantôme CDMAM, a montré que les paramètres optimisés fournissent une détection similaire ou acceptable par rapport à la mammographie standard, à l’exception de l'indication de dépistage lorsque l’on considère les objets de très petits diamètres.L’étude de lecture humaine d’images simulées d’un fantôme anthropomorphique du sein incluant le rehaussement glandulaire physiologique et différents modèle tumoraux n’a pas montré d’augmentation significative de sensibilité de détection des acquisition 3D d’angiotomosynthèse comparativement aux acquisitions 2D d’angiomammographie. Les deux paramètres qui influençaient le plus la sensibilité était la concentration en iode des tumeurs et la densité du sein. L’angiomammographie était par ailleurs significativement plus spécifique que l’angiotomosynthèse. Une perspective d’amélioration pour l’angiotomosynthèse pourrait donc être l’utilisation d’algorithmes de reconstruction 3D spécifiques de cette modalité qui minimiseraient le bruit de… Advisors/Committee Members: Müller, Serge (thesis director).

Subjects/Keywords: Angiomammographie; Optimisation; Mammographie spectrale; Double-énergie; Tomosynthèse mammaire; Angiotomosynthèse mammaire; Biopsie mammaire; CDMAM; Image qualité; Fantôme mammaire; Angio-mammography; Optimization; Spectral mammography; Dual-energy; Breast Tomosynthesis; Breast angiosynthesis; Breast Biopsy; CDMAM; Image quality; Breast phantom

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Dromain, C. (2015). Optimisation de l’angiomammographie et de l’angiotomosynthèse double-énergie : Optimization of contrast enhanced digital mammography and contrast enhanced digital breast tomosynthesis. (Doctoral Dissertation). Université Paris-Sud – Paris XI. Retrieved from http://www.theses.fr/2015PA112019

Chicago Manual of Style (16th Edition):

Dromain, Clarisse. “Optimisation de l’angiomammographie et de l’angiotomosynthèse double-énergie : Optimization of contrast enhanced digital mammography and contrast enhanced digital breast tomosynthesis.” 2015. Doctoral Dissertation, Université Paris-Sud – Paris XI. Accessed December 13, 2019. http://www.theses.fr/2015PA112019.

MLA Handbook (7th Edition):

Dromain, Clarisse. “Optimisation de l’angiomammographie et de l’angiotomosynthèse double-énergie : Optimization of contrast enhanced digital mammography and contrast enhanced digital breast tomosynthesis.” 2015. Web. 13 Dec 2019.

Vancouver:

Dromain C. Optimisation de l’angiomammographie et de l’angiotomosynthèse double-énergie : Optimization of contrast enhanced digital mammography and contrast enhanced digital breast tomosynthesis. [Internet] [Doctoral dissertation]. Université Paris-Sud – Paris XI; 2015. [cited 2019 Dec 13]. Available from: http://www.theses.fr/2015PA112019.

Council of Science Editors:

Dromain C. Optimisation de l’angiomammographie et de l’angiotomosynthèse double-énergie : Optimization of contrast enhanced digital mammography and contrast enhanced digital breast tomosynthesis. [Doctoral Dissertation]. Université Paris-Sud – Paris XI; 2015. Available from: http://www.theses.fr/2015PA112019

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