Otimização de imagem de torax para radiografia computadorizada

Pós-graduação em Biologia Geral e Aplicada - IBB

Estrutura eletrônica do polímero orgânico conjugado MEH-PPV em solução sob radiação ionizante

Pós-graduação em Ciência e Tecnologia de Materiais - FC

Avaliação da dose de radiação absorvida em exames radiológicos durante o planejamento radioterápico

Pós-graduação em Pesquisa e Desenvolvimento (Biotecnologia Médica) - FMB

Método de pontos interiores no planejamento ótimo do tratamento de câncer por radioterapia

The Medical Physics has been developing very fast due to the progress of the technologies and to the increase of the concerns with cure of diseases. One of the Medical Physics main performances at the present time is the use of ionizing radiations for cancer treatment, especially, services as Radiotherapy. The radiotherapy technique uses ionizing radiation with therapeutic end of cancer controls, avoiding your proliferation and it worsens of the patient. For the treatment a radiation bunch is used, with rectangular form, that it passes through the different types of tissues of the patient's body, and depending on the attenuation and of the depth of the fabrics, a great amount of energy is deposited inside in different points of the body. Like this, to plan this treatment type it should be obtained the dimension of the distribution and dose absorption along the volume. For this, it is necessary in the planning of the treatment of the cancer for radiotherapy to build isodose curves, which are lines that represent points of same amount of dose to be deposited in the area to be treated. To aid the construction of the curves of form isodose to reach the best result in the planning of the treatment, in other words, a great planning, providing the maximum of dose in the tumor and saving the healthy and critical organs, it has been using mathematical tools and computational. A plan of cancer treatment for radiotherapy is considered great when all the parameters that involve the treatment, be them physical or biological, they were investigated and adapted individually for the patient. For that, is considered the type and the location of the tumor, worrying about the elimination of the cancer without damaging the healthy tissue of the treated area, mainly the risk organs, which are in general very sensitive to the radiations. This way, the optimization techniques... (Complete abstract click electronic access below)

Estudo de parâmetros radiométricos e legislação sobre radioproteção em equipamentos de radiodiagnóstico

O uso de radiações ionizantes (R.I.), nas mais variadas atividades tem aumentado nas últimas décadas. Com o avanço tecnológico, novos e sofisticados equipamentos emissores de R.I. tem surgido no cenário nacional, o que torna imperativo a difusão do conhecimento sobre os conceitos de proteção radiológica junto à comunidade em geral, e neste sentido, o curso de física médica desenvolve um importante papel, quer seja no aspecto informativo quanto formativo de cidadãos e profissionais críticos e politicamente corretos, que possam contribuir com as Políticas Públicos dos órgãos normatizadores e fiscalizadores das atividades de vigilância sanitária. Conforme a legislação atual (Resolução SS-625 de 14/12/1994, da Secretaria de Estado da Saúde, e Portaria 453 de 01/06/1998 da Vigilância Sanitária do Ministério da Saúde), todos os serviços que utilizam radiações ionizantes devem realizar testes de avaliação dos parâmetros radiométricos dos equipamentos emissores de R.I., sendo exigidos as medidas de Levantamento Radiométrico das instalações, o Teste de Radiação de Fuga do cabeçote emissor e a implementação de Programa de Garantia de Qualidade dos equipamentos e dos procedimentos radiológicos. Este procedimento tem como objetivo principal a obtenção de imagens radiográficas com qualidade e a segurança de pacientes e profissionais, evitando a exposição desnecessária à radiação de pacientes e profissionais. A correta realização de procedimentos radiológicos além de reduzir a dose nos pacientes também promove significativa diminuição nos custos, por não haver necessidade da repetição dos exames. No Brasil, conforme dados da Secretaria de Atenção à Saúde SAS/MS, atualmente existem instalados 4.469 mamógrafos, 25.930 aparelhos de raios-x médicos, 39.438 aparelhos de raios-x odontológicos e...(Resumo completo, clicar acesso eletrônico abaixo)

Uma avaliação do uso do NCRP 151 na realidade brasileira

Medical Physics is an interdisciplinary field that applies concepts and laws of physics in medical practices. Currently, one of its main applications is the use of ionizing radiation in the treatment of oncological diseases. Due to its wide use and highly dangerous, many of radioprotection procedures should be adopted with the objective of protecting human beings from harmful effects of radiation. Thus, you can better enjoy the benefits that the practice can offer. The methodology proposed by the National Council on Radiation Protection 151 (NCRP 151), relates technical information necessary to Structural Shielding Design and Evaluation for Megavoltage X- and Gamma- Ray Radiotherapy Facilities. However, many parameters used to calculate the shield are based on estimates only, and it is an international standard that may not be adequate to the Brazilian reality. Thus, the central idea of this study is the collection of data from the routine of the Radiotherapy Service of the Real e Benemérita Associação Portuguesa de Beneficência, in particular equipment cobalt therapy Theratron 780 (Atomic Energy of Canada Ltd.) and the linear accelerator Varian Clinac 2100C for measurement of workload, number of patients, fields, and dose factors to determine the best use of barrier protection. Furthermore, this work features a profile of radiotherapy treatments carried out closer to the Brazilian reality

Aplicação dos princípios de radioproteção em medicina nuclear

The Nuclear Medicine is a medical specialty which uses different radioisotopes for diagnostic and therapeutic purposes. The isotopes are radioactive elements which are administered in vivo and present distribution to specific organs or cell types. The knowledge of radioactivity and notions related to ionizing radiation allow to contextualize the radiological protection measures to be taken in Nuclear Medicine. So it is possible to minimize unnecessary exposure to patients, the public, and individuals occupationally exposed and the environmental. For this it is necessary to relate the physical and technological bases apply to this mode with the standards established by regulatory agencies, including the CNEN (National Nuclear Energy Commission) and ANVISA (National Agency for Sanitary Vigilance). In this scenario, it is important that the theoretical endorse the activities which are periodically audited for verification of compliance with the standards that aim to radioprotection. One role of the Medical Physicist in these services is, therefore, act as Radiation Protection Supervisor exerting numerous activities and ensuring compliance with these standards. In this context the stage in the area of Nuclear Medicine was developed in many customers of the enterprise Rad Dimenstein & Associados LTDA, among them the hospitals Israelita Albert Einstein (HIAE), Nossa Senhora de Lourdes (HNSL), Santa Paula (HSP), Cruz Azul (CRAZ), Grupo Fleury, among other clinics. Following the routine and then carrying out various activities pertaining to the Medical Physicist in the area, it was noted that the measures and actions are extremely effective and fundamental in terms of radiological protection

Análise do plano de radioproteção em radioterapia

Ionizing radiation is used nowadays in various sectors such as agriculture, industry and medicine. The main specialties of medicine which use radiation are the diagnostic radiology, nuclear medicine and radiotherapy. Radiotherapy is a therapeutic modality that is a well established feature for the treatment of malignant disease or not. However, the inadvertent use of ionizing radiation can produce deleterious effects that result in sequels that compromise the welfare of the people involved. The analysis of radiological protection emphasizes the importance of avoiding inappropriate exhibitions aimed at protecting the health of patients, the professionals involved and the general public. The basic principles of radioprotection are justification, optimization and restriction for individual dosage. The departments of radiotherapy are regulated in accordance with specific technical standards of the National Commission of Nuclear Energy (CNEN), which during the inspection for issue and renewal of the authorization of operation requires the submission of a radioprotection plan, this document that requires great demand of time, and has generated much debate among professionals in medical physics, given the difficulties encountered in their preparation. After examining the radioprotection plan of some radiotherapy services, as suggested in order to guide those responsible for drawing up these plans, especially beginners in the career of the physics of radiation, this paper presents a model plan that is in line radioprotection it requires the Technical Standards of CNEN and can easily be the reality of appropriate services

Uso do método de Monte Carlo para simulação e detecção do espectro de raios-X gerado com feixes de elétrons em alvo de Molibdênio, utilizando o Geant4

The huge demand for procedures involving ionizing radiation promotes the need for safe methods of experimentation considering the danger of their biological e ects with consequent risk to humans. Brazilian's legislation prohibits experiments involving this type of radiation in humans through Decree 453 of Ministry of Health with determines that such procedures comply with the principles of justi cation, optimization and dose limitation. In this line, concurrently with the advancement of available computer processing power, computing simulations have become relevant in those situations where experimental procedures are too cost or impractical. The Monte Carlo method, created along the Manhattan Project duringWorldWar II, is a powerful strategy to simulations in computational physics. In medical physics, this technique has been extensively used with applications in diagnostics and cancer treatment. The objective of this work is to simulate the production and detection of X-rays for the energy range of diagnostic radiology, for molybdenum target, using the Geant4 toolkit. X-ray tubes with this kind of target material are used in diagnostic radiology, speci cally in mammography, one of the most used techniques for screening of breast cancer in women. During the simulations, we used di erent models for bremsstrahlung available in physical models for low energy, in situations already covered by the literature in earlier versions of Geant4. Our results show that although the physical situations seems qualitatively adequate, quantitative comparisons to available analytical data shows aws in the code of Geant4 Low Energy source

Distribuição e dispersão dos níveis radiométricos do setor técnico de medicina nuclear do hospital das clínicas da faculdade de medicina de botucatu

Nuclear medicine uses non-sealed sources for exams and treatments, because the movement of these sources, source of patients injected or not, involve a wide range of environmental radiometric levels. To better control of these levels this study was aimed at monitoring points strategically distributed in all environments Sector Technical Nuclear Medicine, Hospital of the Botucatu Medical School, performing two measurements at random times daily for a period of three months, sampling the normal routine of the sector. The detector Geiger-Muller was used for the acquisition of exposure rates of the points, efficiency and reprodutibility test have shown good performance of this equipment for this purpose. The results allowed to make a projection of annual dose for each environment indicating higher risks for Occupationally Exposed Individuals as well as Public Individuals compared with the limits established by the National Commission of Nuclear Energy. Was developed a spatial map of dose that can be used as a visual warning to the regions with the highest exposure to ionizing radiation, enabling reduced risk of a potential exposure

Programação linear no planejamento do tratamento de câncer por radiocirurgia

Medical Physics has been reaching an important role among several lines in Science, providing means for the improvement of several theories and procedures. Currently, its main application is related with the use of ionizing radiations, specially, in treatment procedures such as Radiotherapy. Radiosurgery is a Radiotherapy technique which consists in administering a single tumoricidal dose of radiation exclusively to the tumorous lesion. It becomes then an interesting alternative to surgical treatment, mainly in cerebral metastases, which are the most frequent cerebral tumors in the central nervous system. The radio neurosurgical team works out a planning for the Radiosurgery treatment, aiming for obtaining an appropriate ideal treatment for each case. For the working out of this treatment planning, Computed Tomography images of the region to be treated are obtained, digitalized and later, fused with nuclear magnetic resonance images. Through these images, critical structures, organs at risk and lesions are localized. After this, calculations are made to determine three-dimensional positions of isocenters, isodose curves, prescribed dose, collimators sizes, position, numbers and respective weight of isocentric conformal fields, and others. The treatment planning is commonly based in desired levels of dose for specific types of tumors and organs at risk concerning the irradiated region. Theses levels of dose are chosen in a way that a high probability of cure may be achieved and meanwhile, that the probability of complications, in whichever organ at risk, may be minimal. Thus, many researches have been carried out, showing that mathematical techniques may help to obtain an optimal planning for the treatment of cerebral metastases. Among the methods of optimization in the study...(Complete abstract click electronic access below)

Aplicações práticas de proteção radiológica nas áreas de medicina nuclear e radiodiagnóstico em instalações hospitalares

After the discovery of ionizing radiation, its applications in various fields of science began to take significant proportions. In the case of medicine, there are the application areas in radiotherapy, diagnostic radiology and nuclear medicine. It was then necessary to create the field of radiological protection to establish the conditions necessary for the safe use of such ionizing radiation. Apply knowledge obtained during the graduation stage and in the practice of radiological protection in the areas of nuclear medicine and diagnostic radiology. In the area of nuclear medicine, tests were made in the Geiger-Muller counters (GM) and the dose calibrator (curiometer), the monitoring tests of radiation, waste management, clean of the Therapeutic room and testing the quality control of gamma-chambers. In the area of radiology, were performed tests of quality control equipment for conventional X-ray equipment and x-ray fluoroscopy, all following the rules of the National Health Surveillance Agency (ANVISA), and reporting of tests. The routine developed in the fields of nuclear medicine in hospitals has proved very useful, since the quality control of GM counters contribute to the values of possible contamination are more reliable. The control of dose calibrator enables the patient not to receive different doses of the recommended amounts, which prevents the repetition of tests and unnecessary exposure to radiation. The management of waste following the rules and laws established and required for its management. Tests for quality control of gamma chambers help to evaluate its medical performance through image. In part of diagnostic radiology, tests for quality control are performed in order to verify that the equipment is acceptable for usage or if repairs are needed. The knowledge acquired at the internship consolidated the learning of graduation course

Estudo neuroanatômico do éncefalo bovino por ressonância magnética

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Radioterapia em medicina veterinária: princípios e perspectivas

This work presents a brief historical about the use of ionizing radiations in Veterinary Medicine, instructing the physical beginnings and techniques wrapped in the realization of the proceedings of radiotherapy in animals, illustrating some treated cases, highlighting the difficulties and pointing to the perspectives and importance of the acting of the medical physics in this kind of therapeutic still little used in the national scenery.

Propriedades luminescentes de polioxometalato contendo európio(III) correlacionadas à sua conformação em sólido estendido e em filmes auto-organizados de Langmuir e Langmuir-Blodgett

Pós-graduação em Química - IQ