Alguns aspectos da Avaliação da Qualidade da Ima-gem em Tomografia Computadorizada
DOI:
https://doi.org/10.15392/bjrs.v5i3.294Keywords:
Escala Hounsfield, Número de TC, coeficiente de determinação.Abstract
A avaliação da qualidade da imagem de tomógrafos inclui a medição dos valores Hounsfield, HU, utilizando uma tabela com os valores limites. Esta tabela não considera que equipamentos diferentes possuem energias efetivas diferentes, o que pode causar resultados falso negativos. Um estudo com 90 tomógrafos computadorizados, com a metodologia do American College Radiology demonstrou que alguns aparelhos reprovados na avaliação apresentaram excelente ajuste linear entre os valores dos coeficientes de atenuação linear calculados para a energia efetiva utilizada, em função dos valores HU. A análise do coeficiente de determinação sugere que 10 destes equipamentos poderiam ter sido aprovados.
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