2D IMRT QA passing rate dependency on coronal plane.
Phys Med
; 110: 102594, 2023 Jun.
Article
em En
| MEDLINE
| ID: mdl-37116388
ABSTRACT
Intensity modulated radiation therapy (IMRT) delivery involves a complex series of beam angles and multileaf collimator (MLC) arrangements, requiring quality assurance to be performed to validate delivery before treatment. The purpose of this work is to investigate the effect of dose gradient on quality assurance (QA) passing rate. Many (n = 40) IMRT plans were delivered and measured using a 2D planar array of ion chambers; additionally, eleven plans were measured at several coronal planes. For each measurement, dose gradient was assessed using a number of metrics and passing rate assessed at both 3%/3 mm and 3%/2 mm criteria. The passing rates of the various IMRT plans were shown to be generally correlated to gradient, with an average distance correlation of 0.54 ± 0.04 for the lateral dose gradient. The passing rate for an individual plan was shown to vary with coronal slice, though the correlation to dose gradient was not predictable. Even though the passing rate was strongly related to dose gradient for many of the plans, the signs of the correlations were not always negative, as hypothesized. The coronal plane at which QA is performed affects passing rate, though dose gradient may not easily be used to predict slices at which passing rate is higher.
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Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Radioterapia de Intensidade Modulada
Tipo de estudo:
Prognostic_studies
Idioma:
En
Ano de publicação:
2023
Tipo de documento:
Article