OPTIMIZATION OF AN ADDITIONAL COLLIMATOR IN A BEAM DELIVERY SYSTEM FOR REDUCTION OF THE SECONDARY NEUTRON EXPOSURE IN PASSIVE CARBON-ION THERAPY.
Radiat Prot Dosimetry
; 184(1): 28-35, 2019 Jul 01.
Article
em En
| MEDLINE
| ID: mdl-30339247
ABSTRACT
The aim of this work is to optimize an additional collimator in a beam delivery system to reduce neutron exposure to patients in passive carbon-ion therapy. All studies were performed by Monte Carlo simulation assuming the beam delivery system at Heavy-Ion Medical Accelerator in Chiba. We calculated the neutron ambient dose equivalent at patient positions with an additional collimator, and optimized the position, aperture size and material of the collimator to reduce the neutron ambient dose equivalent. The collimator located 125 and 470 cm upstream from the isocenter could reduce the dose equivalent near the isocenter by 35%, while the collimator located 813 cm upstream from the isocenter was ineffective. As for the material of the collimator, iron and nickel could conduct reduction slightly better than aluminum and polymethyl methacrylate. The additional collimator is an effective method for the reduction of the neutron ambient dose equivalent near the isocenter.
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Base de dados:
MEDLINE
Assunto principal:
Algoritmos
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Planejamento da Radioterapia Assistida por Computador
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Método de Monte Carlo
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Imagens de Fantasmas
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Radioterapia com Íons Pesados
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Nêutrons
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article