Couch modeling optimization for tomotherapy planning and delivery.
J Appl Clin Med Phys
; 20(8): 114-121, 2019 Aug.
Article
em En
| MEDLINE
| ID: mdl-31343831
ABSTRACT
We sought to validate new couch modeling optimization for tomotherapy planning and delivery. We constructed simplified virtual structures just above a default setting couch through a planning support system (MIM Maestro, version 8.2, MIM Software Inc, Cleveland, OH, USA). Based on ionization chamber measurements, we performed interactive optimization and determined the most appropriate physical density of these virtual structures in a treatment planning system (TPS). To validate this couch optimization, Gamma analysis and these statistical analyses between a three-dimensional diode array QA system (ArcCHECK, Sun Nuclear, Melbourne, FL, USA) results and calculations from ionization chamber measurements were performed at 3%/2 mm criteria with a threshold of 10% in clinical QA plans. Using a virtual model consisting of a center slab density of 4.2 g/cm3 and both side slabs density of 1.9 g/cm3 , we demonstrated close agreement between measured dose and the TPS calculated dose. Agreement was within 1% for all gantry angles at the isocenter and within 2% in off-axis plans. In validation of the couch modeling in a clinical QA plan, the average gamma passing rate improved approximately 0.6%-5.1%. It was statistically significant (P < 0.05) for all treatment sites. We successfully generated an accurate couch model for a TomoTherapy TPS by interactively optimizing the physical density of the couch using a planning support system. This modeling proved to be an efficient way of correcting the dosimetric effects of the treatment couch in tomotherapy planning and delivery.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Garantia da Qualidade dos Cuidados de Saúde
/
Planejamento da Radioterapia Assistida por Computador
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Radioterapia de Intensidade Modulada
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Posicionamento do Paciente
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Modelos Teóricos
/
Neoplasias
Tipo de estudo:
Etiology_studies
/
Prognostic_studies
Limite:
Humans
Idioma:
En
Revista:
J Appl Clin Med Phys
Assunto da revista:
BIOFISICA
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Japão