DANIEL VILLANI
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Artigo IPEN-doc 28208 Development of a 3D printed anthropomorphic skull phantom for clinical photons beam dosimetry2021 - ALMEIDA, S.B.; VILLANI, D.; CAMPOS, L.L.Artigo IPEN-doc 27200 Comparison between Al2O3:C pellets and DIODEs for TSEB in vivo dosimetry using an anthropomorphic phantom2020 - ALMEIDA, S.B.; VILLANI, D.; SAKURABA, R.K.; REZENDE, A.C.P.; CAMPOS, L.L.The Total Skin Electron Beam (TSEB) therapy is a technique that aims to provide skin surface homogeneous absorbed dose in order to treat cutaneous T-cell lymphomas, both for curative and palliative purposes with electron beams penetrating a few millimeters into the skin, reaching the affected parts without affecting internal organs. In vivo dosimetry has become an important role for the treatment of total skin irradiation within a rigorous quality assurance. The luminescent dosimeters, such as TLDs and OSLDs, have proven to be very useful for the verification of the dose distribution and prescribed for the patient as the dose may differ from place to place due to patient body geometry, overlapping of structures and asymmetries of the radiation field. Other routine in vivo dosimetry tool is the DIODEs and they as well help validating radiation therapy dosimetry. Al2O3:C OSL pellets manufactured and marketed by REXON Components and TLD Systems have already been characterized for TSEB applications. The aim of this work is to compare the performance of Al2O3:C OSL pellets from REXON to in vivo TSEB dosimetry with silicon DIODEs QEDTM detectors from Sun Nuclear (EUA) using an anthropometric phantom. Dosimeters and DIODEs were previously characterized for 6 MeV HDTSe- electron beams and then placed over an Anderson Rando® anthropomorphic phantom, evaluating the body dose distribution. The reference point of measurement was the umbiculous as recommended by formalism. The results showed that the Al2O3:C OSL pellets presented acceptable results, but some greater variation of the response in relation to silicon DIODEs were found due to its considerable rotational dependency.Artigo IPEN-doc 26092 Dosimetric evaluation employing TL and OSL techniques with different luminescent materials for clinical evaluation of extremity doses using electron beams applied to Total-Irradiation-of-Skin treatments2018 - ALMEIDA, SHIRLANE B. de; VILLANI, DANIEL; SAKURABA, ROBERTO K.; REZENDE, ANA C.P. de; SANTOS, SILAS C.; CAMPOS, LETICIA L.Total-skin electron beam (TSEB) irradiation is used to deliver a homogeneous dose distribution over the entire skin surface of a patient. TSEB dosimetry is quite complex as to the evaluation and measurement of absorbed dosage in the cutaneous region. This paper evaluates the performance of different dosimetric materials, using TL and OSL dosimetry, in the extremity-dose assessment of TSEB treatments using the six-dual-field technique and an anthropomorphic phantom. Dosimeters were selected with repeatability better than ±5.0% and calibrated to 6-MeV electron-beam dosimetry. Measurements were conducted in the abdominal region as a reference point and on the extremities. Results show expected deviations ranging up to 20% in the dose received in the extremities and good results in dose assessment using all dosimetric materials tested.Resumo IPEN-doc 26019 Comparison between Al2O3:C pellets and DIODEs for TSEB in vivo dosimetry using an anthropomorphic phantom2018 - ALMEIDA, S.B.; VILLANI, D.; SAKURABA, R.K.; REZENDE, A.C.P.; CAMPOS, L.L.Artigo IPEN-doc 25760 Dosimetric evaluation and comparation of TL responses of LiF:Mg,Ti and μLiF:Mg,Ti in the clinical electron beams dosimetry applied to total skin irradiation (TSEB) treatments2019 - ALMEIDA, S.B.; VILLANI, D.; SAKURABA, R.K.; REZENDE, A.C.P.; CAMPOS, L.L.The Total Skin Electron Beam (TSEB) irradiation is a radiotherapeutic technique that aims to provide the patient's skin surface with a more homogeneous dose, in order to treat cutaneous T-cell lymphomas, both for curative and palliative purposes. Electron irradiation penetrates a few millimeters into the skin, reaching the affected parts completely, without penetrating the internal organs. In vivo dosimetry has become an important role for the treatment of total skin irradiation within a rigorous quality assurance program that should be an integral part of the radiotherapy departments. The use of TLDs in vivo can identify variations in the prescribed dose because its measurement accuracy and great precision. The LiF:Mg,Ti is the most used TL material and widely studied in radiotherapy dosimetry due to near tissue-equivalence of the material, along with its overall reliability. The dosimeters of μLiF:Mg,Ti have been gaining considerable importance in the radiotherapy departments. These detectors allow measurements in vivo with great advantages due to their minimum dimensions of 1×1×1 mm3. This paper reports a comparative study of the TL responses of both materials to dose evaluation in TSEB treatments. The TL response of both materials in several TSEB parameter tests and in clinical application were evaluated, analyzing the dose distribution in a treatment simulation using AldersonRando anthropomorphic phantom. The results showed that the μLiF:Mg,Ti presented greater variation of the response in relation to LiF dosemeters in some parameters analyzed, due to the small dimensions and to evaluate doses absorbed in the surface over a large area in the treatment plan.Artigo IPEN-doc 25048 Comparative study of the TL response of LiF:Mg,Ti and CaSO4:Dy in the clinical electron beams dosimetry applied to total skin irradiation (TSEB) treatments2019 - ALMEIDA, S.B.; VILLANI, D.; SAKURABA, R.K.; REZENDE, A.C.P.; CAMPOS, L.L.The commissioning and quality assurance The Total Skin Electron Beam (TSEB) irradiation treatment is based on the AAPM's report 23, which describes the six-dual-field (Standford) technique, and the Hospital Israelita Albert Einstein (HIAE) follows this recommended guidance. The Dosimetric Materials Laboratory of the Instituto de Pesquisas Energéticas e Nucleares (IPEN-LMD) has tradition in research related to thermoluminescent materials and its clinical applications. Thus, aiming to apply the LiF:Mg,Ti, the most common TLD material, and CaSO4:Dy + Teflon produced at IPEN as easy-to-use alternatives to electron beams dosimetry and its parameters applied to TSEB, this paper reports a comparative study of the TL responses of both materials to dose evaluation in TSEB treatments. The TL response of both materials was evaluated in several TSEB parameter tests such as clinical field homogeneity, Monitor Units (MU) calculation, absorbed doses over the reference line and throughout the surface of the skin in a treatment simulation using AldersonRando anthropomorphic phantom. Results show that the field homogeneity measurements remained within ± 8% acceptance limit from AAPM Report 23, little to no energy dependency over the range of 4 o 9 MeV electron beams and, for clinical measurements and MU calculations, both TLDs present compatible results and can be used as alternative tools in TSEB dosimetry.Artigo IPEN-doc 24675 TL and OSL dosimetric characterization of different luminescent materials for clinical electron beams application in TSEB treatments2018 - ALMEIDA, S.B.; VILLANI, D.; SAKURABA, R.K.; REZENDE, A.C.P.; CAMPOS, L.L.Thermoluminescent dosimeters (TLDs) play an important role in radiotherapy for the dosimetry of ionizing radiation. This type of dosimeter presents advantages that makes them a useful tool for measurements in anthropomorphic phantoms and in vivo dosimetry. Several dosimetric materials have been used in the radiotherapy sectors such as LiF, μLiF, CaSO4:Dy. The OSL dosimetry has also been widely applied using Aluminum Oxide (Al2O3:C). These dosimeters have advantages over TLDs due to their high sensitivity, extensive linearity in response to the dose, faster reading, possibility of multiple readings and the need to perform the heat treatment of the samples. The aim of this work was to compare and characterize, using TL and OSL techniques, different luminescent dosimeters (LiF, μLiF, CaSO4:Dy and Al2O3:C) to be applied in clinical electron beam used to TSEB treatments. Measurements were performed in order to study the applicability of these detectors as easy-to-take alternatives to calibration and measurements of TSEB treatments. Parameters such as dose-response curves; average sensitivity to radiation, intrinsic efficiency and energy and angular dependences were evaluated. The results show good agreement within CaSO4:Dy and TLD-100 measurements and, applying energy and angle dependence factors over the other two materials, all the four detectors can be applied as alternative easy-to-take dosimetric tools for commissioning and quality assurance of 6 MeV clinical electron beams used in TSEB treatments.Artigo IPEN-doc 22882 Resposta de Microcubos de TLD-100TM a dois feixes de qualidade RQR32016 - NUNES, M.G.; VILLANI, D.; ALMEIDA, S.B.; VIVOLO, V.; YORIYAZ, H.; LOUIS, G.M.J.A resposta de microcubos de TLD-100TM a dois feixes de qualidade RQR 3, definida pela norma IEC-61267, é comparada para que a dependência da resposta do TLD-100TM com a energia efetiva do feixe de radiação X reportada na literatura seja avaliada nessas condições. A reprodutibilidade dos microcubos de TLD-100TM é avaliada através da resposta de um segundo conjunto de dosímetros, obtida em uma segunda leitora, ao feixe implementado no Laboratório de Calibração de Instrumentos do IPEN. A dependência da resposta com a energia efetiva ou o espectro do feixe não foi detectada e a reprodutibilidade das medidas é de 90,2%.Artigo IPEN-doc 23751 Caracterização de dosímetros de Al2O3:C para dosimetria de fótons utilizando a técnica OSL2016 - VILLANI, D.; ALMEIDA, S.B.; CAMPOS, L.L.A dosimetria opticamente estimulada (OSL) tem ganhado destaque em aplicações clínicas e acadêmicas no Brasil. Nesse trabalho, são apresentados resultados da caracterização OSL dos dosímetros de Al2O3:C (TLD-500) fabricados pela Rexon™ Components and TLD Systems em uma leitora RISØ, modelo TL/OSL-DA-20 para dosimetria de feixes de fótons de energias altas. Todos os parâmetros da leitora, e suas variações foram avaliados.