Breast cancer remains a leading cause of mortality among women, with molecular subtypes significantly influencing prognosis and treatment strategies. Currently, identifying the molecular subtype of cancer requires a biopsy—a specialized, expensive, and time-consuming procedure, often yielding to results that must be supported with additional biopsies due to technique errors or tumor heterogeneity. This study in...
Microcalcification clusters (MCs) are one of the most important biomarkers for breast cancer and Digital Breast Tomosynthesis (DBT) has consolidated its role in breast cancer imaging. As there are mixed observations about MCs detection using DBT, it is important to develop tools that improve this task. Furthermore, the visualization mode of MCs is also crucial, as their diagnosis is associated with their 3D mor...
Microcalcification clusters (MCs) are one of the most important biomarkers for breast cancer and Digital Breast Tomosynthesis (DBT) has consolidated its role in breast cancer imaging. As there are mixed observations about MCs detection using DBT, it is important to develop tools that improve this task. Furthermore, the visualization mode of MCs is also crucial, as their diagnosis is associated with their 3D mor...
Cancer is a major health concern and the prognosis is often poor. Significant advances in nanotechnology are now driving a revolution in cancer detection and treatment. The goal of this study was to develop a novel hybrid nanosystem for melanoma treatment, integrating therapeutic and magnetic targeting modalities. Hence, we designed long circulating and pH-sensitive liposomes loading both dichloro(1,10-phenanth...
In a wide range of medical fields, technological advancements have led to an increase in the average collective dose in national populations worldwide. Periodic estimations of the average collective population dose due to medical exposure is, therefore of utmost importance, and is now mandatory in countries within the European Union (article 12 of EURATOM directive 97/43). Presented in this work is a report on ...
Este estudo foi realizado num Hospital, em Lisboa, onde foram avaliados 30 exames tomográficos de tórax. Com a realização deste trabalho, pretendeu-se quantificar o nível de referência de dose num dos equipamentos de TC de um Hospital de Lisboa, incidindo na avaliação do estudo do tórax. Pretendeu-se ainda, quantificar um valor médio para as grandezas dosimétricas em tomografia computorizada, nomeadamente o CTD...
A radiossenssibilidade em crianças é superior à dos adultos, pelo que a avaliação dos parâmetros de dose utilizados em pediatria, principalmente em recém-nascidos, assume particular importância. Também importante é a avaliação da quantidade de dose de radiação a que os pacientes, pelo simples facto de estarem perto, ou na vizinhança, de outros que vão realizar exames radiológicos, estão sujeitos. Neste estudo, ...
A radiossensibilidade de crianças, muito superior à dos adultos, aliada à elevada utilização de exames radiológicos, justifica a preocupação com as doses à entrada da pele (DEP) e doses efectivas (DEF) durante exames radiológicos pediátricos. Neste trabalho quantificou-se a DEP e a DEF em sistemas convencionais e digitais em exames abdominais em crianças dos 0-15 anos, comparando os parâmetros físicos utilizado...
O avanço das tecnologias nos últimos anos promoveu a passagem de muitos serviços para sistemas de digitalização indirecta e directa, substituindo os sistemas convencionais de películas. As evidências mostram que os sistemas de digitalização de imagem deveriam possibilitar reduções nas doses utilizadas num determinado exame radiológico, mas na prática, nem sempre a dose é menor que a dos sistemas de películas. E...
The Clear-PEM system is a prototype scanner for Positron Emission Mammography (PEM), currently under development. In the scope of this project, we present the implementation of three iterative algorithms for 2D image reconstruction, using linograms: the Algebraic Reconstruction Technique (ART), the Maximum Likelihood Expectation Maximization (ML-EM) and the Ordered Subsets Expectation Maximization (OS-EM) algor...