Dosimetric comparison of absolute and relative dose distributions between tissue maximum ratio and convolution algorithms for acoustic neurinoma plans in Gamma Knife radiosurgery.
Acta Neurochir (Wien)
; 156(8): 1483-9; discussion 1489, 2014 Aug.
Article
em En
| MEDLINE
| ID: mdl-24890937
ABSTRACT
BACKGROUND:
The treatment planning for Gamma Knife (GK) stereotactic radiosurgery (SRS) that performs dose calculations based on tissue maximum ratio (TMR) algorithm has disadvantages in predicting dose in tissue heterogeneity. The latest version of the planning software is equipped with a convolution dose algorithm as an optional extra and the new algorithm is able to compensate for head inhomogeneity. However, the effect of this improved calculation method requires detailed validation in clinical cases. In this study, we compared absolute and relative dose distributions of treatment plans for acoustic neurinoma between TMR and the convolution calculation.METHODS:
Twenty-nine clinically used plans created by TMR algorithm were recalculated by convolution method. Differences between TMR and convolution were evaluated in terms of absolute dose (beam-on time), dosimetric parameters including target coverage, selectivity, conformity index, gradient index, radical homogeneity index and the dose-volume relationship.RESULTS:
The discrepancy in estimated absolute dose to the target ranged from 1 to 7 % between TMR and convolution. In addition, dosimetric parameters of the two methods achieved statistical significance. However, it was difficult to see the change of relative dose distribution by visual assessment on a monitor.CONCLUSIONS:
Convolution, heterogeneity correction calculation, and the algorithm are necessary to reduce the dosimetric uncertainty of each case in GK SRS.
Texto completo:
1
Coleções:
01-internacional
Temas:
Geral
/
Tipos_de_cancer
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Outros_tipos
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Tratamento
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Radioterapia
Base de dados:
MEDLINE
Assunto principal:
Planejamento da Radioterapia Assistida por Computador
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Neuroma Acústico
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Radiocirurgia
Tipo de estudo:
Health_economic_evaluation
Limite:
Humans
Idioma:
En
Revista:
Acta Neurochir (Wien)
Ano de publicação:
2014
Tipo de documento:
Article