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Master's Dissertation
DOI
10.11606/D.18.2009.tde-17112009-084935
Document
Author
Full name
Larissa Cristina dos Santos Romualdo
Institute/School/College
Knowledge Area
Date of Defense
Published
São Carlos, 2009
Supervisor
Committee
Vieira, Marcelo Andrade da Costa (President)
Gonzaga, Adilson
Silva, Ana Maria Marques da
Title in Portuguese
Restauração de imagens mamográficas digitais utilizando o filtro de Wiener no domínio de Anscombe e o filtro inverso da MTF no domínio da frequência
Keywords in Portuguese
Filtro de Wiener
Função de transferência de modulação
Mamografia
Processamento de imagens
Transformada de Anscombe
Abstract in Portuguese
Este trabalho tem por objetivo o desenvolvimento de uma nova técnica de pré-processamento de imagens mamográficas digitais para melhorar o desempenho dos esquemas computacionais de auxílio ao diagnóstico (CAD) e para auxiliar na detecção precoce do câncer de mama. O método proposto efetua uma restauração nas imagens mamográficas utilizando, em uma primeira etapa, a transformada de Anscombe e o filtro de Wiener para redução do ruído quântico. Posteriormente, é utilizado o filtro inverso da função de transferência de modulação (MTF) do sistema de imagem para realce das estruturas de interesse na mamografia, como as microcalcificações, que podem ser um indicativo de câncer de mama em seu estágio inicial. Imagens mamográficas restauradas pelo método proposto foram utilizadas na avaliação de um esquema CAD para detecção automática de microcalcificações. Os resultados mostraram que o desempenho do esquema CAD apresentou uma melhora significativa quando imagens restauradas foram utilizadas, mesmo para imagens de mamas densas, que resultam normalmente em baixa taxa de detecção devido ao baixo contraste.
Title in English
Digital mamographic images restoration using Wiener filter in Anscombe domain and inverse MTF filter in frequency domain
Keywords in English
Anscombe transform
Image processing
Mammography
Modulation transfer function
Wiener filter
Abstract in English
This work aims to developing a new technique for pre-processing digital mammographic images in order to improve the performance of computer aided-diagnosis schemes (CAD) and to assist in early detection of breast cancer. The proposed method performs a restoration in mammographic images using in a first step, the Anscombe transform and Wiener filtering to reduce image quantum noise. Subsequently, it was used the inverse modulation transfer function filtering (MTF) considering the imaging system to enhance structures of interest in mammography, such as microcalcifications, which may be an indicative of breast cancer in its early stage. Mammographic images restored by the proposed method were used in the evaluation of a CAD scheme for automatic detection of microcalcifications. The results showed that the performance of the CAD scheme had a significant improvement when restored images were used, even for images of dense breasts, which often results in low detection rate due to low contrast.
 
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Larissa.pdf (4.56 Mbytes)
Publishing Date
2009-11-24
 
WARNING: The material described below relates to works resulting from this thesis or dissertation. The contents of these works are the author's responsibility.
  • ROMUALDO, Larissa Cristina dos Santos, VIEIRA, Marcelo Andrade da Costa, and SCHIABEL, Homero. Mammography Images Restoration by Quantum Noise Reduction and Inverse MTF Filtering [doi:10.1109/SIBGRAPI.2009.12]. In 2009 XXII Brazilian Symposium on Computer Graphics and Image Processing [online], Rio de Janiero, Brazil, 2009. Rio de Janiero, Brazil : IEEE, 2009. p. 180-185. ISBN 978-1-4244-4978-1.
  • DöSSEL, Olaf, and SCHLEGEL, Wolfgang C.. World Congress on Medical Physics and Biomedical Engineering, September 7 - 12, 2009, Munich, Germany [doi:10.1007/978-3-642-03882-2_213]. Editor. Berlin, Heidelberg : Springer Berlin Heidelberg, 2010. chap. 213, Enhancement of Breast Images by Noise Reduction and MTF Compensation to Improve Microcalcifications Detection, p. 801-804. IFMBE Proceedings.
All rights of the thesis/dissertation are from the authors
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