Detecção Automática do Teste de Winston-Lutz em Filmes Radiocrômicos
DOI:
https://doi.org/10.29384/rbfm.2020.v14.19849001515Keywords:
Garantia da qualidade, Radiocirurgia, Teste de Winston-Lutz, Filme radiocrômicoAbstract
Radiocirurgia estereotáxica é uma técnica altamente precisa para entrega de altas doses em um pequeno volume alvo utilizando alto gradiente de dose, exigindo precisão submilimétrica na localização e entrega de dose. Para garantir acurácia requerida, recomenda-se a verificação do alinhamento do eixo de rotação do gantry, mesa e colimador, realizada através do teste de Winston-Lutz (WL). O teste de WL realizado através de filmes é tradicionalmente analisado visualmente, mostrando-se com variabilidade inter e intra-observador. Tal limitação pode ser evitada através da digitalização dos filmes e uso de software para análise. Uma vez que o uso de filmes em programas de garantia da qualidade para radiocirurgia ainda é uma realidade comum em muitos centros de radioterapia, o objetivo deste estudo foi desenvolver um algoritmo para análise do teste de WL realizado com filme de forma tridimensional, objetiva e reprodutível. Pela análise dos resultados, o algoritmo desenvolvido conseguiu detectar com precisão o deslocamento obtido a partir do teste de WL utilizando filmes radiocrômicos de forma tridimensional, mostrando forte potencial para ser utilizado clinicamente. Sua implementação possibilita redução da subjetividade e variabilidade da análise devido à automatização do processo, possibilitando criação automática de relatórios para o programa de garantia de qualidade em radiocirurgias.
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