Browsing by Author "Fernandes, Paulo"
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- A comparative dosimetric study between free-breathing and forced inspiration used radiotherapy 3D techniques in the left breast cancerPublication . Duarte, Mónica; Rodrigues, Vanessa; Caetano, Marco; Fernandes, Paulo; Bak, BartosABSTRACT: Introduction – Radiotherapy (RT) is a therapeutic approach for the treatment of left breast cancer. However, different breathing techniques free breathing (FB) and deep inspiration breath-hold (DIBH) can be used. Objectives – To identify which of the breathing techniques, DIBH or FB, has obtained better irradiation of the planning target volume (PTV) and a lower dose at the organs at risk (OAR). Check if the DIBH technique allows a dose reduction in the left ventricle. Methodology – Twenty female patients with pathology in the left breast were selected. In computed tomography, the contours of PTV and OAR were made. We obtained dosimetric data for each patient, with each of the two types of breathing techniques. Dosimetric data for all patients were compared for both respiratory techniques. Results – The DIBH technique reduced the mean dose (Dmean) and V20% in the left lung, only being higher in four patients. In the left ventricle, there was a decrease in Dmean and V30% in all patients. The spinal cord in either DIBH or FB did not reach the reference limit, however, there was an improvement when using DIBH. Conclusions – The DIBH technique presents lower doses in the organs at risk, improvements in PTV dose coverage, as well as conformity, homogeneity, and quality indexes when compared to the FB technique.
- Controlo da qualidade dosimétrico no serviço de radioterapia do Hospital CUF Descobertas (HCD): importância do controlo da qualidade do sector da física e resultados da auditoria ESTRO-EQUALPublication . Jacob, Katia; Rosa, Maria João; Ferreira, Paulo; Oliveira, Susana; Sousa, Mónica; Fernandes, Paulo; Parafita, R.; Teixeira, Nuno; Ramalho, Miguel; Rodrigues, RuiA calibração e o controlo da qualidade de um acelerador linear são passos muito importantes num serviço de Radioterapia, para garantir a qualidade dos tratamentos prestados. O sector da Física da Unidade de Radioterapia do Hospital Cuf Descobertas implementou um rigoroso Programa de controlo de qualidade ao equipamento produtor de radiação e aos equipamentos medidores de radiação, de acordo com o Dec-Lei 180/2002 e com os protocolos internacionais. Para tal, foram implementados procedimentos, criadas folhas de cálculo, instruções de trabalho e impressos. Foram ainda implementados testes aos equipamentos com periodicidade definida: controlo de qualidade diário e controlo de qualidade após intervenções (manutenções preventivas e correctivas). No decorrer do ano de 2005, o sector da Física colaborou activamente com toda a equipa da Radioterapia na implementação da Norma ISO 9001:2000 no serviço, contribuindo com o seu know how na implementação desta, numa área tão importante como a da garantia da qualidade dos feixes de radiação e das respectivas calibrações em dose. Numa procura de melhoria contínua da qualidade dos serviços prestados aos pacientes, decorre ainda uma auditoria externa da EQUAL-ESTRO*, intercomparação postal com dosímetros termoluminescentes. A qualidade dos feixes de energias utilizados diariamente é analisada, tanto ao nível das calibrações absolutas de cada um dos feixes de fotões e de electrões, como ao nível dos cálculos de dose obtidos com o sistema de planimetria XiO da CMS. Os resultados das duas primeiras fases da intercomparação, relativa aos dois feixes de fotões de 6 MV e 15 MV e feixes de electrões de 4 MeV, 8 MeV e 12 MeV, foram considerados pela EQUAL-ESTRO num nível óptimo (desvio máximo na dose medida em relação à dose de referência |d| ≤ 3%).
- MobiWise: eco-routing decision support leveraging the internet of thingsPublication . Aguiar, Ana; Fernandes, Paulo; Guerreiro, Andreia P.; Tomás, Ricardo; Agnelo, João; Santos, José Luís; Araújo, Filipe; Coelho, Margarida C.; Fonseca, Carlos M.; D'Orey, Pedro; Luís, Miguel; Sargento, SusanaEco-routing distributes traffic in cities to improve mobility sustainability. The implementation of eco-routing in real-life requires a diverse set of information, including different kinds of sensors. These sensors are often already integrated in city infrastructure, some are technologically outdated, and are often operated by multiple entities. In this work, we provide a use case-oriented system design for an eco-routing service leveraging Internet-of-Things (IoT) technologies. The methodology involves six phases: (1) defining an eco-routing use case for a vehicle fleet; (2) formulating a routing problem as a multi-objective optimisation to divert traffic at a relevant hub facility; (3) identifying data sources and processing required information; (4) proposing a microservice-based architecture leveraging IoT technologies adequate to a multi-stakeholder scenario; (5) applying a microscopic traffic simulator as a digital twin to deal with data sparsity; and (6) visually illustrating eco-routing trade-offs to support decision making. We built a proof-of-concept for a mid-sized European city. Using real data and a calibrated digital twin, we would achieve hourly total emissions reductions up to 2.1%, when applied in a car fleet composed of 5% of eco-routing vehicles. This traffic diversion would allow annual carbon dioxide and nitrogen oxides savings of 400 tons and 1.2 tons, respectively.