Estudo comparativo de câmaras de ionização de dois diferentes volumes sensíveis para controle de qualidade da dose em IMRT
DOI:
https://doi.org/10.29384/rbfm.2014.v8.n1.p27-30Abstract
O objetivo desse trabalho é fazer um estudo comparativo das câmaras de ionização com volumes sensíveis de 0.01 cm3 e 0.13 cm3 para realização do controle da dose absorvida para o tratamento de Radioterapia de Intensidade Modulada (IMRT). Para realização desse estudo foram selecionados 20 planejamentos de IMRT com tamanhos de campos de até 9,8 x 9,8 cm2, e para cada planejamento, foram feitas medidas de dose com ambas as câmaras, sendo estas posicionadas em uma região de baixo gradiente de dose. Os dados medidos foram comparados com os dados fornecidos pelo software de planejamento. As análises das medidas mostraram que ambas as câmaras podem ser utilizadas para dosimetria de controle de qualidade de IMRT, pois foram obtidas variações inferiores a 4,5% do valor esperado, sendo que a câmara com volume de 0.13 cm3 apresentou melhores resultados. Pode-se concluir que a câmara 0.13 cm3, apesar de ter um volume maior, é mais propicia para dosimetria de controle de qualidade de IMRT, não descartando também o uso da câmara de volume 0.01 cm3 que obteve resultados satisfatórios.
Downloads
References
Hong, T., Ritter, M., Harari, P. (2005). Intensity-modulated radiation therapy: Emerging cancer treatment technology. British Journal of Cancer. 92, 1819-1824.
ICRU (2010).International Commission on Radiation Units and Measurements. Prescribing, Recording and Reporting Photon Beam IMRT. ICRU Report 83 (International Commission on Radiation Units and Measurements, Geneva, Switzerland).
Low, D., Moran, J.M., Dempsey, J. F., Dong, L., Oldham, M. (2010). Dosimetry tools and techniques for IMRT. Med. Phys. 38, 0094-2405
Sanchez-Doblado, F., Hartmann, G. H., Pena, J., Capote, R., Paiusco, M., Rhein, B., Leal, A., and Lagares, J. I. (2007). Uncertainty estimation in intensity-modulated radiotherapy absolute dosimetry verification. Int. J. Radiat. Oncol. Biol Phys. 68, 301–310.
IAEA (2000). International Atomic Energy Agency. Absorbed Dose Determination in External Beam Radiotherapy: An International Code of Practice for Dosimetry Based on Absorbed Dose to Water. IAEA TRS-398 (International Atomic Energy Agency, Vienna).
Arno J.M., John C. R. . Intensity modulated radiation therapy – Clinical Perspective. BC Decker Inc; 2005, p. 186-204.
Intensity Modulated Radiation Therapy Collaborative Working Group. Intensity modulated radiotherapy: current status and issues of interest. Int J Radiat Oncol Biol Phys 2001; 51:880–914.
Ezzell GA, Galvin JM, Low D, et al. Guidance document on delivery, treatment planning, and clinical implementation of IMRT. Report of the IMRT Subcommittee of the AAPM Radiation Therapy Committee. Med Phys 2003;30:2089–115
Moran JM. Dosimetry metrology for IMRT. In: Palta JR, Mackie TR, editors. Intensity-modulated radiation therapy: the state of the art. Colorado Springs (CO):Medical Physics Publishing; 2003. p. 415–37.
Martens C., DeWagter C., DeNeve W. . The value of the PinPoint ion chamber for characterization of small field segments used in intensity-modulated radiotherapy. Phys Med Biol 2000;45:2519–30.
Low DA, Parikh P, Dempsey JF, et al. Ionization chamber volume averaging effects in dynamic intensity modulated radiation therapy beams. Med Phys 2003;30:1706–11.
Laub W. , Wong T. The volume effect of detectors in the dosimetry of small fields used in IMRT. Med Phys 2003;30:341–7.
Downloads
Published
How to Cite
Issue
Section
License
The submission of original articles to the Brazilian Journal of Medical Physics implies the transfer, by the authors, of the rights of print and digital publication. Copyright for published articles remains with the author, with journal rights on first publication. Authors may only use the same results in other publications by clearly indicating this journal as the original publisher. As we are an open access journal, free use of articles in educational, scientific, non-commercial applications is allowed, as long as the source is cited.
The Brazilian Journal of Medical Physics is under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0).
