LUCAS VERDI ANGELOCCI

LUCAS VERDI ANGELOCCI

Página do item completo

Resultados de Busca

Agora exibindo 1 - 7 de 7

Characterization of the anisotropy function of a new 125I brachytherapy source using thermoluminescent dosimetry
2024 - NOGUEIRA, THUANY C.; ANGELOCCI, LUCAS V.; SANTOS, HAMONA N. dos; TALACIMON, CRISTHIAN F.; TEODORO, LARA E.H.; RIGO, MARIA E.Z.; RODRIGUES, PRISCILA S.; BURIN, ANA L.; ZEITUNI, CARLOS A.; ROSTELATO, MARIA E.C.M.
A dosimetric evaluation using the Monte Carlo method considering geometric variations of the iodine-125 seed for brachytherapy
2024 - CHICO, H.S.; ANGELOCCI, L.V.; ZEITUNI, C.A.; SOUZA, C.D.; SGRIGNOLI, S.S.; ROSTELATO, M.E.C.M.
Estimation of dose deposition by 198-AuNPs in the prostate with MCNP in simplified geometry
2024 - SGRIGNOLI, S.S.; ANGELOCCI, L.V.; CHICO, H.S.; SOUZA, C.D.; BURIN, A.L.; RODRIGUES, P.S.; TEODORO, L.E.H.; MEDEIROS, I.M.M.; ZEITUNI, C.A.; ROSTELATO, M.E.C.M.
End-weld thickness variation effects on dose rate for a new ir-192 brachytherapy source
2019 - ANGELOCCI, LUCAS V.; NOGUEIRA, BEATRIZ R.; ABREU, RODRIGO T.; ZEITUNI, CARLOS A.; ROSTELATO, MARIA E.C.M.
Brachytherapy is a form of radiation therapy that uses small sealed sources close to the tumor to deliver a high dose to target while keeping dose on neighboring healthy tissues as low as possible. A wide variety of radionuclides and different sources are available for brachytherapy, each with his own unique geometry. The Laboratory of Sources Production for Radiotherapy (IPEN/CNEN) developed a new Ir-192 seed for eye tumor treatment that is currently under dosimetric definition. This work is part of a larger project that aims the full dosimetry of this new source, but rather than calculate the usual parameters proposed by the American Association of Physicists in Medicine, the specific contribution to the dose rate of a usually not considered factor was investigated under a statistical approach: end-weld thickness variation, which is important due to this source being welded by an in-house method. Its effects were investigated using the Monte Carlo radiation transport code MCNP4C and an in-house routine programmed with MATLAB® to analyze the data. Final results are presented as a mean value for dose rate at different points of interest and their associated standard deviations. The results are discussed based on the influence of said parameter on different points around the source.
Anisotropy function of a new 192-Ir brachytherapy source
2019 - ABREU, RODRIGO T.; ANGELOCCI, LUCAS V.; NOGUEIRA, BEATRIZ R.; SANTOS, HAMONA N. dos; ZEITUNI, CARLOS A.; ROSTELATO, MARIA E.C.M.
Brachytherapy is a type of radiotherapy that uses radioactive sources (seeds, wires, among others) close to the tumor. Is important to provide a detailed description of seed dosimetry, so only the tumor will be irradiated avoiding unnecessary dose on adjacent organs and structures. To evaluate the dosimetric parameter of the anisotropy function for a new brachytherapy source, this work proposes the use of microcube TLD-100 dosimeters to find the dose rate using the AAPM Task Group 43 protocol (TG-43). The anisotropy function represents dose distribution around the source and has a major role for characterization of a new iridium source being implemented in Brazil. The value of D(r,θ) was measured using Solid Water phantoms, r value being the distance from the geometric center of the source to the position of the dosimeter on the phantom, and θ being the angle formed between the longitudinal axis of the source and the line connecting the geometric center to the TLD. Monte Carlo calculations were performed to evaluate the anisotropy function to validate the experimental measurements. For each distance value (r), an anisotropy function was plotted (1.0, 2.0, 3.0, 4.0, 5.0, and 10.0 cm). The results obtained with Monte Carlo calculations agreed ±2% with the experimental values for r greater than 3.0 cm, so these results show a good distribution of dose around the seed considering the high energy of 192-Ir (average of 380 KeV) and encapsulation thickness.
Dose-rate constant and air-kerma strength evaluation of a new 125-I brachytherapy source using Monte-Carlo
2019 - PRIMO, CAMILA de O.; ANGELOCCI, LUCAS V.; KARAM JUNIOR, DIB; ZEITUNI, CARLOS A.; ROSTELATO, MARIA E.C.M.
Brachytherapy is a modality of radiotherapy which treats tumors using ionizing radiation with sources located close to the tumor. The sources can be produced from several radionuclides in various formats, such as Iodine-125 seeds and Iridium-192 wires. In order to produce a new Iodine-125 seed in IPEN/CNEN and ensure its quality, it is essential to describe the dosimetry of the seed, so when applied in a treatment the lowest possible dose to neighboring healthy tissues can be reached. The report by the AAPM’s Task Group 43 U1 is a document that indicates the dosimetry procedures in brachytherapy based on physical and geometrical parameters. In this study, dose-rate constant and air-kerma strength parameters were simulated using the Monte Carlo method radiation transport code MCNP4C. The air-kerma strength is obtained from an ideal modeled seed, since its actual value should be measured for seeds individually in a specialized lab with a Wide-Angle Free-Air Chamber (WAFAC). Dose-rate constant and air-kerma strength are parameters that depends on intrinsic characteristics of the source, i.e. geometry, radionuclide, encapsulation, and together they define the dose-rate to the reference point, defined as the dose-rate to a point 1 cm away from the geometric center of the source, in its transverse plane. This study presents the values found for these parameters with associated statistical uncertainty, and is part of a larger project that aims the full dosimetry of this new seed model, including experimental measures.
Human eye analytical and mesh-geometry models for opthtalmic dosimetry using MCNP6
2015 - ANGELOCCI, LUCAS V.; FONSECA, GABRIEL P.; YORIYAZ, HELIO