A virtual linear accelerator for verification of treatment planning systems.
Phys Med Biol
; 45(10): 2887-96, 2000 Oct.
Article
en En
| MEDLINE
| ID: mdl-11049178
A virtual linear accelerator is implemented into a commercial pencil-beam-based treatment planning system (TPS) with the purpose of investigating the possibility of verifying the system using a Monte Carlo method. The characterization set for the TPS includes depth doses, profiles and output factors, which is generated by Monte Carlo simulations. The advantage of this method over conventional measurements is that variations in accelerator output are eliminated and more complicated geometries can be used to study the performance of a TPS. The difference between Monte Carlo simulated and TPS calculated profiles and depth doses in the characterization geometry is less than +/-2% except for the build up region. This is of the same order as previously reported results based on measurements. In an inhomogeneous, mediastinum-like case, the deviations between TPS and simulations are small in the unit-density regions. In low-density regions, the TPS overestimates the dose, and the overestimation increases with increasing energy from 3.5% for 6 MV to 9.5% for 18 MV. This result points out the widely known fact that the pencil beam concept does not handle changes in lateral electron transport, nor changes in scatter due to lateral inhomogeneitics. It is concluded that verification of a pencil-beam-based TPS with a Monte Carlo based virtual accelerator is possible, which facilitates the verification procedure.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Aceleradores de Partículas
/
Radiometría
/
Planificación de la Radioterapia Asistida por Computador
Tipo de estudio:
Health_economic_evaluation
/
Prognostic_studies
Idioma:
En
Revista:
Phys Med Biol
Año:
2000
Tipo del documento:
Article
País de afiliación:
Suecia
Pais de publicación:
Reino Unido