Simulação computacional do fantoma Angelika usando o método Monte Carlo

Abstract

This study investigated the dose distribution in an phisical phantom using Monte Carlo simulations with two modeling approaches: mesh surfaces, generated with Blender software, and Macrobodies, created with Vised software. The simulations analyzed vertical and horizontal trajectories of a radiation source, focusing on dosimetric accuracy and the influence of the phantom's geometry on the results. EBT3 films were strategically positioned inside and on top of the phantom to evaluate the angular and longitudinal distribution of dose rates. The results showed that both methodologies are effective but have distinct characteristics. The Macrobody model exhibited more uniform and predictable dose distributions, especially for vertical trajectories, making it suitable for analyses in simplified geometries. In contrast, the mesh model was more sensitive to geometric heterogeneities and allowed for the identification of dose peaks in horizontal positions, capturing local variations with greater precision. Discrepancies between the methods, such as differences in dose rates in the horizontal plane, were attributed to gaps or deformations in the modeling, suggesting the need for geometric adjustments. The conclusion highlights that both methodologies are complementary and useful depending on the study's objective. While the Macrobody method is ideal for quick and consistent simulations, the mesh method is more detailed and suitable for analyses requiring greater geometric realism. The research underscores the importance of the Monte Carlo method as a tool for prediction and adjustment before the physical fabrication of phantoms, significantly contributing to advancements in radiological applications, brachytherapy treatment planning, and dosimetric system validation.