Análise gama e medida de dose pontual, baseado na metodologia de controle estatístico de processo
DOI:
https://doi.org/10.29384/rbfm.2019.v13.n3.p8-14Keywords:
Radioterapia, Controle da Qualidade Paciente-específico, Controle estatístico de processosAbstract
Controles da qualidade paciente-específico têm sido utilizados constantemente, como forma de garantir que os planejamentos de radioterapia que utilizam técnicas de intensidade volumétrica modulada (VMAT) sejam reproduzidas de forma adequada pelos aceleradores lineares. A principal dificuldade neste processo é elaborar limites de tolerância e de ação institucionais, que permitam uma análise mais acurada e traduzam a confiabilidade e executabilidade desses tratamentos. Este trabalho buscou estabelecer os limites de tolerância e ação para casos de VMAT, utilizando a metodologia de controle estatístico de processo, dividindo os casos de acordo com cada acelerador linear e com cada sítio anatômico. Foram analisados para cada caso o índice gama e a medida de dose pontual, assim como o intervalo de confiança de 95%, após a atualização do sistema de planejamento da instituição. Os intervalos de confiança encontrados mostraram-se dentro da faixa esperada, quando comparados com outras instituições. Com relação à aplicação do controle estatístico de processo, foi possível elaborar i-charts para cada sítio anatômico e traçar perfis de aprovação para o índice gama e as medidas de dose pontual para cada caso. A implementação deste protocolo mostrou-se válida, tornando a análise do controle da qualidade paciente-específico mais importante e menos subjetiva dentro da instituiçãoDownloads
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