VICENTE DE PAULO DE CAMPOS
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Artigo IPEN-doc 24780 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 dosimeters2019 - 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.Artigo IPEN-doc 11932 Leaked filters for energetic an angular dependence corrections of thermoluminescent response2007 - MANZOLI, JOSE E.; CAMPOS, VICENTE de P. de; SHAMMAS, GABRIEL I.J.Artigo IPEN-doc 09887 Selecionamento de detectores de radiacao segundo sua sensibilidade e viabilidade para dosimetria termoluminescente2003 - MANZOLI, J.E.; CAMPOS, V.P.Artigo IPEN-doc 17494 Assessment of CaSOsub(4):Dy thermoluminescent detectors response for different phantom materials and proton energies2011 - ROCHA, FELICIA DEL G.; CAMPOS, VICENTE de P. de; CAMPOS, LETICIA L.Artigo IPEN-doc 15007 Determination of radiation direction in environmental monitoring2009 - CAMPOS, VICENTE de P. de; MOURA, EDUARDO S.; ROCHA, FELICIA D.G.; MANZOLI, JOSE E.Artigo IPEN-doc 12161 Assessment of the ambiental exposure at IPEN using CASOsub(4):Dy detectors with different filters combination2007 - CAMPOS, VICENTE de P. de; ROCHA, FELICIA D.G.; RODRIGUES, LETICIA L.C.Artigo IPEN-doc 11618 Evaluation of reproductibility and detection limit of CaSOsub(4):Dy radiation detectorsemission spectrometry after wet partial digestion and neutron activation analysis2006 - MANZOLI, JOSE E.; CAMPOS, VICENTE de P. de; DOI, MIRIAN S.Measurement response of thermoluminescent dosimeter, TLD, used by workers or placed at positions where gamma radiation field could be in action affecting biological tissues, should be completely characterized, in order to achieve the radiation quantity with precision and confidence. Among the evaluations concerned to its characterization, the detector reproductibility is of fundamental importance, because detectors present inside the TLD will be used many times in routine. Reproductibility is studied by repeated exposure to the same radiation field. The minimum detection limit is another important characteristics of a TLD. In this work evaluations of reproductibility and minimum detection are presented, for dosimeters produced at IPEN.