Computational analysis of 'Dose/Collision Kerma' relationship and lateral boundary in Stereotatic circular fields using EGSnrc.

Authors

  • Reginaldo Gonçalves Leão Center for Research in Physics and Engineering Applied to Health/ Federal Institute of Minas Gerais, Arcos, Brazil
  • Rômulo Verdolin de Sousa São João de Deus Hospital, Divinópolis, Brazil
  • Arno Heeren de Oliveira Department of Nuclear Engineering/Federal University of Minas Gerais, Belo Horizonte, Brazil
  • Hugo Lemos Leonardo Silva Santa Casa Hospital, Belo Horizonte, Brazil
  • Arnaldo Prata Mourão Biomedical Engineering Center/Federal Center for Technological Education of Minas Gerais, Belo Horizonte, Brazil

DOI:

https://doi.org/10.29384/rbfm.2016.v10.n1.p2-8

Keywords:

Small Fields, Dosimetry, Monte Carlo, EGSnrc

Abstract

Objectives: This work aimed to obtain data from small fields of X-rays that evidence of the hypotheses cited as cause of difficulties for the dosimetry of these. For this purpose, the verification of compatibility between the dosimetric boundary of field and the geometric size of field, was performed. Also was made, the verification of kerma dose according to the expected relationship for conventional fields. Materials and Methods: Computer simulations of smaller fields 5x5 cm² were performed using the Monte Carlo method by egs_chamber application, this derived from EGSnrc radiation transport code. As particulate sources were used phase space files of a Clinac 2100 head model coupled to cones Stereotactic Radiosurgery. Results: The simulations suggested the existence of a plateau in discrepancies between the dose FWHM and the nominal diameter of the field close to 8%. These simulations also indicated a decrease of these values for fields with diameters smaller than 12 mm and larger than 36 mm. Simultaneously, the dose kerma differences in depth reached values higher than 14% in the case where the phenomenon is more significant.  Conclusion: The data showed that in fact the behavior of small fields clashes with that expected for conventional fields, and that the traditional dosimetric conventions do not apply to such fields requiring a specialized approach to the techniques that employ them. Furthermore, the existence of the aforementioned plateau of discrepancies, along with the decrease thereof in less than 15 mm diameter fields constitute a remarkable finding.

Downloads

Download data is not yet available.

Author Biographies

Reginaldo Gonçalves Leão, Center for Research in Physics and Engineering Applied to Health/ Federal Institute of Minas Gerais, Arcos, Brazil

Físico Licenciado pela UNIFORMG, especialista em Física pela UFLA, Mestre em Ciência das Radiações pelo DEN/UFMG, Doutorando em Ciência das Radiações pelo DEN/UFMG. Docente do Curso de Engenharia Elétrica no IFMG

Rômulo Verdolin de Sousa, São João de Deus Hospital, Divinópolis, Brazil

Doutorado em Físico-Química pela Universidade Federal de Minas Gerais-UFMG (2009), Pós-Doutorado em Físico-Química pela Universidade Federal de Minas Gerais-UFMG (2010) e 2 Pós-Doutorados em Engenharia Nuclear pela Universidade Federal de Minas Gerais-UFMG (2013 e 2015). É especialista em Física Médica de Radioterapia pela Associação Brasileira de Física Médica (ABFM) e Supervisor de Radioproteção pela Comissão Nacional de Energia Nuclear (CNEN). Atua como físico médico responsável e como supervisor titular de proteção radiológica no Serviço de Radioterapia do Hospital São João de Deus em Divinópolis-MG.

Arno Heeren de Oliveira, Department of Nuclear Engineering/Federal University of Minas Gerais, Belo Horizonte, Brazil

Professor Titular do Departamento de Engenharia Nuclear da Universidade Federal de Minas Gerais, atua no Programa de Pós-Graduação em Ciências e Técnicas Nucleares, nos cursos de Mestrado e Doutorado, Pesquisador 1C do CNPq, graduado em Física pela Universidade Federal do Paraná (1976), Mestrado em Ciências e Técnicas Nucleares pela Universidade Federal de Minas Gerais (1979), Diplome d´Eudes Aprofondie (1981) no Institut National et Polytechinique de Grenoble /França e Doutorado em Genie Atomique (1984) no Institut National et Polytechinique de Grenoble. Pós- Doutorado na área de Dosimetria (Dosimetria de Neutrons), no Centre d´Etudes Nucleáires de Grenoble/CEA(1987), Pós doutorado em Aplicação de Raioisótopos (Métodos Nucleares) no Centre d´Etudes Nucleaires de Saclay/CEA (1997), Participação em projeto de pesquisa da Comunidade Européia no Laboratoire de Biphysique-Université Paris XII (1998), Pós Doutorado em Química Analítica no Service Central d´Analyse de Lyon/CNRS(2004) 

Hugo Lemos Leonardo Silva, Santa Casa Hospital, Belo Horizonte, Brazil

Bacharel em Física pela Universidade Federal de Minas Gerais (2004) , Mestre em Ciência e Tecnologia das radiações, Minerais e Materiais pelo Centro de Desenvolvimento da Tecnologia Nuclear CDTN/ CNEN (2006). Atualmente é Físico - Médico e Supervisor de Radioproteção do Hospital Santa Casa de Misericórdia de Belo Horizonte

Arnaldo Prata Mourão, Biomedical Engineering Center/Federal Center for Technological Education of Minas Gerais, Belo Horizonte, Brazil

Professor Titular do Centro Federal de Educação Tecnológica de Minas Gerais, graduado em Engenharia Elétrica pelo Centro Federal de Educação Tecnológica de Minas Gerais (1987), mestre em Engenharia Elétrica pela Universidade Federal de Minas Gerais (1995) e doutor em Ciências Técnicas Nucleares pela Universidade Federal de Minas Gerais (2008). Atualmente é avaliador de cursos de graduação pelo INEP, Colaborador do Centro de Desenvolvimento da Tecnologia Nuclear e Professor Permanente no Programa de Pós-graduação em Ciências e Técnicas Nucleares do Departamento de Engenharia Nuclear da UFMG. Tem experiencia em Engenharia Elétrica com foro em Conversão e retificação de energia elétrica e atua nas seguintes áreas: Automação, Máquinas Elétricas, Fontes Alternativas de Energia, Radiologia, Dosimetria das radiações, Imagens Médicas, Tomografia computadorizada, Monte Carlo, Dosimetria e Braquiterapia.

References

Sean MM, Douglas SW, Bonnie H et al. Hypofractionated Stereotactic Body Radiotherapy in Low-Risk Prostate Adenocarcinoma, Nuclear Instruments and Methods in Physics Research A . 2012, 118, 3681-90.

Yasushi N, Yoshiharu N, Tetsuya A, et al. Clinical Outcomes of 3D Conformal Hypofractionated Single High-Dose Radiotherapy for one or Two Lung Tumors Using A Stereotactic Body Frame, Radiation Oncology Biology and Physics, 2002, 52, 1041-6.

Daniel AL, Jean MM, James FD, et al. Dosimetry tools and techniques for IMRT, 2011, Medical Physics, 38, 1313-38.

Sonja D, Carlo C, Cynthia FC, et al. Report of AAPM TG 135: Quality assurance for robotic radiosurgery, Medical Physics, 2011, 38, 2914-36.

Michael CS, Frank JB, David AL, et al. Stereotactic Radiosurgery: Report of Task Group 42 - Radiation Therapy, Comittee, American Association of Physicists in Medicine, 2011.

Christos A, Evaggelos P. Performance Evaluation of a CyberKnif Robotic Stereotactic RadioSurgery System, Physics in Medicine and Biology, 2008, 53, 4697-718.

Alfonso R, Andreo P, Huq MS, et al. A new formalism for reference dosimetry of small and nonstandard fields, Medical Physics, 2008, 35, 5179-186.

Indra JD, George XD, Anders A. Small Fields: Nonequilibrium Radiation Dosimetry,

Medical Physics, 2008, 35, 206-15.

Philip M, Alan N, Jean-Claude R. Handbook of Radiotherapy Physics: Theory and Practice, Boca Raton: Taylor & Francis Group; 2007.

C-M CM, Alan N. Bragg Gray theory and ion chamber dosimetry for photon beams, 1991, Physics in Medicine and Biology, 36, 413-28.

Attix FH, De La Vergne L, Ritz VH, Cavity ionisation as a function of wall material, 1958, J. Res. NBS, 60, 235.

Attix FH, The partition of kerma to account for bremsstrahlung, Health Phys, 1979, 36, 347–54.

Stanley HB, David JS, Steven JG, et al. Stereotactic Radiosurgery and Stereotactic Body Radiation Therapy, Boca Raton: Taylor & Francis Group; 2015.

Kawrakow I, Mainegra-Hing E, Rogers DWO, et al. The EGSnrc Code System: Monte Carlo Simulation of Electron and Photon Transport, Ottawa: National Research Council Canada, 2016.

Rogers DWO, Walters B, Kawrakow I, BEAMnrc Users Manual, Ottawa: National Research Council Canada, 2016.

Walters B, Kawrakow I, Rogers DWO. DOSXYZnrc Users Manual, Ottawa: National Research Council Canada, 2016.

Reginaldo GLJr, Arno HO, Rômulo VS, et al. Modeling and Commissioning of a Clinac 600 CD by Monte Carlo method using the BEAMnrc and DOSXYZnrc codes, 2015, INAC, São Paulo.

Reginaldo GLJr, Arnaldo PM, Rômulo VS, et al. Desenvolvimento de Geometria Especialista em Dosimetria Numérica de Pequenos Campos por Método de Monte Carlo, Utilizando o Código EGSNRC, 2016, III SENCIR, Belo Horizonte.

Roesch WC, Dose for nonelectronic equilibrieum conditions, 1958, Radiation Research, 9, 399-410.

Downloads

Published

2017-01-28

How to Cite

Leão, R. G., Sousa, R. V. de, Oliveira, A. H. de, Silva, H. L. L., & Mourão, A. P. (2017). Computational analysis of ’Dose/Collision Kerma’ relationship and lateral boundary in Stereotatic circular fields using EGSnrc. Brazilian Journal of Medical Physics, 10(1), 2–8. https://doi.org/10.29384/rbfm.2016.v10.n1.p2-8

Issue

Vol. 10 No. 1 (2016)

Section

Artigo Original

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).

Creative Commons License

Most read articles by the same author(s)