Performance of a linear accelerator couch positioning quality control task using an electronic portal imaging device.
Radiol Phys Technol
; 13(2): 195-200, 2020 Jun.
Article
em En
| MEDLINE
| ID: mdl-32078138
Short and semi-automated quality assurance (QA) programs are becoming one of the most popular and highly demanding tasks in radiotherapy. The current research investigates the accuracy of a four degrees of freedom (4DoF) medical linear accelerator couch positioning with a fast and accurate method based on images acquired using an electronic portal imaging device (EPID). An accurate EPID QA phantom and a proper in-house code were used. A Siemens medical linear accelerator equipped with an a-Si EPID was used to acquire portal images. For verifying the mechanical performance of the EPID positioning, EPID sensitivity, and accuracy of the code response from the image processing point of view were investigated. To characterize the results, three deviations in the phantom positioning were deliberately created. The translational and rotational displacements of the treatment couch were then evaluated. The loading effect on the treatment couch was then investigated. The results of prerequisite tests, including the mechanical performance of the EPID, and the sensitivity and accuracy of the recognition codes, were assessed. The results were found to be within the tolerance range reported at AAPM TG-142. The mean deviations of the tests between expected and measured displacements by 4DoF treatment couch were found to be 0.13° ± 0.11°, 0.12 ± 0.17 mm, 0.17 ± 0.13 mm, and 0.04 ± 0.09 mm for rotational, longitudinal, lateral, and vertical shifts, respectively. The results showed that the proposed method is a reliable and fast approach to find the uncertainties occurring intreatment couch positioning.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Aceleradores de Partículas
/
Equipamentos e Provisões Elétricas
Idioma:
En
Revista:
Radiol Phys Technol
Assunto da revista:
BIOFISICA
/
RADIOLOGIA
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
Irã
País de publicação:
Japão