Modelagem dos acessórios de imobilização e mesa de tratamento no Sistema de Planejamento Eclipse
DOI:
https://doi.org/10.29384/rbfm.2023.v17.19849001733Keywords:
radiotherapy, attenuation, table top, modeling of strucuturesAbstract
Currently, in treatment planning systems (TPS), some models of structures are offered that may not match reality, because the different regions and structures that compose them have different electronic densities. Therefore, its use may introduce systematic errors in the dose calculation. In this way, the objective of the study was to model the base of the orfit and the Exact couch table top in TPS Eclipse. For this, a computed tomography scan of the base of the Orfit accessories and the Exact Couch table top was performed. Their structures were delineated based on their densities. Attenuation measurements of each structure were performed in a water phantom with an ionization chamber. The Hounsfield unit was varied in the TPS in order to approximate the calculated dose value to the measured value. Initially, the largest discrepancy was up to 6.7%. After modeling the structures, the greatest discrepancy found was 1.3%. After validation of this set of structures, they started to be inserted in the SPT for consideration in the dose calculation.
Keywords: radiotherapy; attenuation; table top; modeling of structures.
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Copyright (c) 2023 Rodrigo Brito Lavoura, Kamille Joana Casagrande, André Vinicius Camargo, Diego C. S. A. da Silva
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