VICENTE DE PAULO DE CAMPOS

VICENTE DE PAULO DE CAMPOS

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Assessment of energy and angular dependence of LiF:Mg,Ti dosimeters irradiated in the quantity Hp(0.07)
2023 - NASCIMENTO, G.G.; SILVA, C.R.; CAMPOS, V.P.; CAMPOS, L.L.
Radiation dosimetry has the purpose of quantifying the dose received by the occupationally exposed individual. The device used in this process is called a dosimeter, the dosimeter can be used in different situations, for example, the dosimeter used to quantify the dose received in the fingers is the ring model dosimeter, for the extremity, which is the focus of this work. In Brazil, we still do not have standards for the calibration of extremity dosimeters, therefore, in this work, the CASEC recommendations were used, adapted for extremity dosimetry. For a dosimeter to be used in its respective routine, it must present results within some preestablished limits in reference standards. For this purpose, energy dependence and angular dependence tests were carried out. To calibrate the LiF:Mg,Ti thermoluminescent dosimeters, a phantom rod was used. The phantom rod has the function of simulating the region of interest, in the case of this work, the fingers. The dosimeters were irradiated in the magnitude Hp(0.07), with the doses and energies recommended by the CASEC standard. The aim of this work is to characterize end dosimeters in the ring model with LiF:Mg,Ti detectors.
Caracterização da reprodutibilidade de detectores de LiF:Mg, Ti utilizando dosímetros termoluminescentes de extremidade no modelo anel do IPEN no rod phantom com irradiações na grandeza Hp(0,07)
2023 - NASCIMENTO, G.; CAMPOS, V.P.; CAMPOS, L.L.
Introdução: A radiologia, em especial a radiologia intervencionista e a medicina nuclear, são as duas principais áreas de exposição do indivíduo ocupacionalmente exposto (IOE), sendo necessário a utilização de dosímetros. Para que um dosímetro possa ser utilizado com certa confiabilidade, é necessário que ele passe por alguns testes de calibração e caracterização. Neste trabalho, o ensaio de reprodutibilidade é realizado seguindo as recomendações do Comitê de Avaliação de Serviços de Ensaio e Calibração (CASEC). Materiais e Métodos: As equações utilizadas nesta sessão são recomendadas pela apostila do CASEC, para dosimetria de corpo inteiro, porém, neste trabalho, adaptadas para dosimetria de extremidade. O rod phantom utilizado neste trabalho pertence ao Laboratório de Calibração de Instrumentos do IPEN (LCI-IPEN). Para as irradiações, foi utilizado um sistema Irradiador Pantak/Seifeirt modelo Isovolt 60 Hs na faixa do radiodiagnóstico. As qualidades N-60, N-80, N-100 e N-150 foram avaliadas neste trabalho. Resultados e Discussões: A média das 10 avaliações da resposta TL apresentou uma baixa variação de resultados para as irradiações de 10 mSv na grandeza Hp(0,07) utilizando 118 keV. Para o ensaio de reprodutibilidade para uma mesma dose, a média das 10 avaliações para uma dose de 10 mSv na grandeza Hp(0,07) com uma energia de 118 keV, apresentou baixa variação da resposta. Conclusões: Os sistemas dosimétricos e sistemas irradiadores apresentaram uma boa reprodutibilidade, tanto em dose avaliada quanto no resultado após a interação com a equação. As irradiações na grandeza Hp(0,07) foram bem sucedidas, confirmando a importância da utilização de um phantom em situações de caracterização e calibração.
Characterization of the reproducibility of LiF:Mg, Ti dosimeters and the radiator system in the quantity Hp(0.07)
2022 - NASCIMENTO, G.; CAMPOS, L.L.; CAMPOS, V.P.
Assessment of energy and angular dependence of LiF:Mg,Ti dosimeters irradiated in the quality Hp(0.07)
2022 - NASCIMENTO, G.G.; SILVA, C.R.; CAMPOS, V.P.; CAMPOS, L.L.
Avaliação da resposta TL em função da dose de dosímetros de LiF:Mg, Ti na grandeza Hp(0,07) utilizando o rod phantom
2022 - NASCIMENTO, GABRIEL G. do; CAMPOS, VICENTE de P. de; RODRIGUES, LETICIA L.C.
Os dosímetros são utilizados para quantificar a dose que o indivíduo ocupacionalmente exposto recebe durante seu período de atividades. O dosímetro de extremidade tem a finalidade de quantificar a dose em uma região específica do corpo, as mãos. Para um dispositivo ser utilizado como dosímetro, ele deve passar por alguns testes de calibração/caracterização, entre eles, o teste de resposta em função da dose, onde o dosímetro é irradiado com diferentes doses no intervalo de interesse recomendado, preferencialmente, deverá apresentar um padrão linear de resposta em função das doses utilizadas. O Hp(0,07) é uma grandeza operacional estabelecida para monitoração individual externa, sendo 0,07 mm a profundidade adotada. Neste trabalho as irradiações foram realizadas na grandeza Hp(0,07) utilizando um rod phantom, com o objetivo de avaliar a resposta TL em função da dose, aplicando os dosímetros de LiF:Mg, Ti.
Characterization and calibration of thermoluminescent dosimeters of LiF:Mg, Ti in the quantity Hp(0.07)
2022 - NASCIMENTO, G.G.; CAMPOS, V.P.; CAMPOS, L.L.
The extremity dosimeters are devices used to quantifying the radiation dose that the occupationally exposed individual receives in specific regions of the body during the work time. Dosimeter calibration is essential so that the dosimeter response is equivalent to the received dose. Tests such as batch homogeneity and lower detection limit are part of the dosimeter calibration process. The rod phantom simulates the region of interest regarding the interaction with radiation and the scattered dose. The extremity dosimeters used were the LiF:Mg,Ti thermoluminescent dosimeters.
Characterization and calibration of thermoluminescent dosimeters of LiF:Mg, Ti in the quantity Hp(0.07)
2021 - NASCIMENTO, G.; CAMPOS, V.; CAMPOS, L.
Analise dosimétrica de um laboratório de radiobiodistribuição in vivo usando CaSO4:Dy
2019 - CAMPOS, R.F.; CAMPOS, V.P.; MITAKE, M.B.; ARAUJO, E.B.
Performance of TL and OSL techniques using CaSO4 and Al2O3 dosimeters for mean glandular dose (MGD) and entrance surface skin dose (ESD) determination in a digital mammographic unit as alternative dosimeters
2019 - ROCHA, F.D.G.; VILLANI, D.; CAMPOS, V.P.; NOGUEIRA, M.S.; GOULART, M.E.; SICHITO, V.A.; CAMPOS, L.L.
The mammography is the most important and simple tool in the diagnosis of breast diseases in women. In digital mammography, the process of image acquisition, display and storage are separated which allows optimization of each. Despite the innumerous advantages of this technique, such as an accurate diagnosis for women with dense breast, it was noticed an increase of radiation doses to obtain the images by this system. As with any examination that includes x-rays, there is always a small stochastic risk of inducing cancer, it is therefore important to evaluate the risk from the dose delivered to the patient during the screening process. The mean glandular dose within the breast is the recommended quantity to evaluate the risk from radiation to the breast. To guarantee proper conditions of protection for patients, the radiation dose should be as low as reasonably achievable possible and simultaneously compatible with image quality requirements. Thus, this work proposes the use of the thermoluminescent (TL) CaSO4:Dy sintered discs, produced at IPEN, widely used in individual, environmental and area monitoring in Brazil, and Al2O3:C optically stimulated luminescence (OSL) ‘dot’ dosimeters, manufactured by Landauer® Inc., as application as easy-to-use and low cost alternative dosimeters to evaluate the entrance skin doses (ESD) delivered to patients, the half value layer (HVL) and the mean glandular doses (MGD) in a mammographic digital unit, comparing these two techniques with the results obtained using an Allin- one QC meter. The results obtained demonstrated that the TL and OSL dosimetry systems and the CaSO4 and Al2O3 dosimeters used are able to evaluate the entrance skin dose as well as mean glandular doses in a digital mammographic unit accurately within the requirements, and they can be considered a practical, simple, easy-touse and low cost tools for verification of these items in a Quality Assurance Program.
Performance of TL and OSL techniques using CaSO4 and Al2O3 Dosimeters for Mean Glandular Dose (MGD) and Entrance Surface Skin Dose (ESD) determination in a digital mammographic unit as alternative dosimeters
2017 - ROCHA, FELICIA D.G.; VILLANI, DANIEL; CAMPOS, VICENTE de P. de; NOGUEIRA, MARIA do S.; GOULART, MAURICIO E.; SICHITO, VALTER; CAMPOS, LETICIA L.
The mammography is the most important and simple tool in the diagnosis of breast diseases in women. In digital mammography, the process of image acquisition, display and storage are separated which allows optimization of each. Despite the innumerous advantages of this technique, such as an accurate diagnosis for women with dense breast, it was noticed an increase of radiation doses to obtain the images by the new system. As with any examination that includes x-rays, there is always a small stochastic risk of inducing cancer. It is therefore important to evaluate the risk from the dose delivered to the patient during the screening process. The mean glandular dose within the breast is the recommended quantity to evaluate the risk from radiation to the breast. To guarantee proper conditions of protection for patients, the radiation dose should be as low as reasonably achievable possible and simultaneously compatible with image quality requirements. Thus, this work proposes the use of the thermoluminescent (TL) CaSO4:Dy sintered discs, produced at IPEN, widely used in individual, environmental and area monitoring in Brazil, and Al2O3:C optically stimulated luminescence (OSL) ‘dot’ dosimeters, manufactured by Landauer® Inc., as application as easy-to-use and low cost alternative dosimeters to evaluate the entrance skin doses (ESD) delivered to patients, the half value layer (HVL) and the mean glandular doses (MGD) in a mammographic digital unit, comparing these two techniques with the results obtained using an All-in-one QC meter. The results obtained demonstrated that the TL and OSL dosimetry systems and the CaSO4 and Al2O3 dosimeters used are able to evaluate the entrance skin dose as well as mean glandular doses in a digital mammographic unit accurately within the requirements, and they can be considered a practical, simple, easy-to-use and low cost tools for verification of these items in a Quality Assurance Program.