Application of a Monte Carlo linac model in routine verifications of dose calculations
Main Article Content
Abstract
The analysis of some parameters of interest in radiotherapy Medical Physics based on an experimentally validated Monte Carlo model of an Elekta Precise lineal accelerator was performed for 6 and 15 MV photon beams. The simulations were performed using the EGSnrc code. As reference for simulations, the values of the previously obtained optimal beam parameters (energy and FWHM) were used. Deposited dose calculations in water phantoms were done, on typical complex geometries commonly are used in acceptance and quality control tests, such as irregular and asymmetric fields. Parameters such as MLC scatter, maximum opening or closing position, and the separation between them were analyzed from calculations in water. Similarly simulations were performed on phantoms obtained from CT studies of real patients, making comparisons of the dose distribution calculated with EGSnrc and the dose distribution obtained from the computerized treatment planning systems used in routine clinical plans. All the results showed a great agreement with measurements, fi nding all of them within tolerance limits. These results allowed the possibility of using the developed model as a robust verifi cation tool for validating calculations in very complex situations, where the accuracy of the available TPS could be questionable.
Article Details
How to Cite
Linares Rosales, H. M., Lara Mas, E., Alfonso Laguardia, R., & Popescu, T. (1). Application of a Monte Carlo linac model in routine verifications of dose calculations. Nucleus, (57). Retrieved from http://nucleus.cubaenergia.cu/index.php/nucleus/article/view/607
Section
Ciencias Nucleares
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
Aquellos autores/as que tengan publicaciones con esta revista, aceptan los términos siguientes:
- Los autores/as conservarán sus derechos de autor y garantizarán a la revista el derecho de primera publicación de su obra, el cuál estará simultáneamente sujeto a la Licencia Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) que permite a terceros compartir la obra siempre que se indique su autor y su primera publicación esta revista. Bajo esta licencia el autor será libre de:
- Compartir — copiar y redistribuir el material en cualquier medio o formato
- Adaptar — remezclar, transformar y crear a partir del material
- El licenciador no puede revocar estas libertades mientras cumpla con los términos de la licencia
Bajo las siguientes condiciones:
- Reconocimiento — Debe reconocer adecuadamente la autoría, proporcionar un enlace a la licencia e indicar si se han realizado cambios. Puede hacerlo de cualquier manera razonable, pero no de una manera que sugiera que tiene el apoyo del licenciador o lo recibe por el uso que hace.
- NoComercial — No puede utilizar el material para una finalidad comercial.
- No hay restricciones adicionales — No puede aplicar términos legales o medidas tecnológicas que legalmente restrinjan realizar aquello que la licencia permite.
- Los autores/as podrán adoptar otros acuerdos de licencia no exclusiva de distribución de la versión de la obra publicada (p. ej.: depositarla en un archivo telemático institucional o publicarla en un volumen monográfico) siempre que se indique la publicación inicial en esta revista.
- Se permite y recomienda a los autores/as difundir su obra a través de Internet (p. ej.: en archivos telemáticos institucionales o en su página web) antes y durante el proceso de envío, lo cual puede producir intercambios interesantes y aumentar las citas de la obra publicada. (Véase El efecto del acceso abierto).
La Revista Nucleus solo aceptará contribuciones que no hayan sido previamente publicados y/o procesados, por otra publicación. Cualquier violación ese sentido será considerada una falta grave por parte del autor principal lo cual será objeto valoración por parte del Consejo Editorial, el cual dictaminará al respecto.
References
[1]. KAWRAKOW I & WALTERS BRB. Effi cient photon beam dose calculations using DOSXYZnrc with BEAMnrc. Med. Phys. 2006; 33(8): 3046-3056.
[2]. TZEDAKIS A, DAMILAKIS JE, MAZONAKIS M, et. al. Influence of initial electron beam parameters on Monte Carlo calculated absorbed dose distributions for radiotherapy photon beams. Med. Phys. 2004; 31(4): 907-913.
[3]. LOBO J & POPESCU IA. Two new DOSXYZnrc sources for 4D Monte Carlo simulations of continuously variable beam configurations, with applications to RapidArc, VMAT, TomoTherapy and CyberKnife. Phys. Med. Biol. 2010; 55(16): 4431-4443.
[4]. ROGERS DWO, WALTERS B & KAWRAKOW I. BEAMnrc Users Manual. Ionizing Radiation Standards. National Research Council of Canada, May 2007.
[5]. KAWRAKOW I, ROGERS DWO & WALTERS BRB. Large efficiency improvements in BEAMnrc using directional bremsstrahlung splitting. Ionizing Radiation Standards National Research Council of Canada. Physics Dept, Carleton University, Ottawa K1S 5B6, 2004.
[6]. WESTERMARK M, ARNDT J, NILSSON B, BRAHME A. Comparative dosimetry in narrow high-energy photon beams. Phys Med Biol. 2000; 45(3): 685-702.
[7]. EKLUND K & AHNESJ OA. Modeling silicon diode energy response factors for use in therapeutic photon beams. Phys Med Biol. 2004; 54(20): 6135-6150.
[8]. YIN Z, HUGTENBURG RP & BEDDOE AH. Response corrections for solid-state detectors in megavoltage photon dosimetry. Phys Med Biol. 2004; 49(16): 3691-3702.
[9]. EKLUND K. Modeling Silicon diode dose response in radiotherapy fields using fluence pencil kernels. PhD thesis. Faculty of Medicine, Uppsala University. Uppsala, 2010. ISBN-978-91-554-7748-6.
[10]. SCOTT A, NAHUM A & FENWICK J. Monte Carlo modeling of small photon fi elds: quantifying the impact of focal spot size on source occlusion and output factors, and exploring miniphantom design for small-fi eld measurements. Medical Physics. 2009; 36(7): 3132-3144.
[11]. HEYDARIAN M, HOBAN PW & BEDDOE AH. A comparison of dosimetry techniques in stereotactic radiosurgery. Phys Med Biol. 1996; 41(1): 93-110.
[12]. ASPRADAKIS M, BYRNE J, PALMANS H, et. al. IPEM Report Number 103: Small field MV photon dosimetry. New York: IPEM, 2010. ISBN: 978-1-903613-45-0.
[13]. ROGERS DWO, WALTERS B & KAWRAKOW I. DOSXYZnrc Users Manual. Ionizing Radiation Standards. National Research Council of Canada, May 2007.
[2]. TZEDAKIS A, DAMILAKIS JE, MAZONAKIS M, et. al. Influence of initial electron beam parameters on Monte Carlo calculated absorbed dose distributions for radiotherapy photon beams. Med. Phys. 2004; 31(4): 907-913.
[3]. LOBO J & POPESCU IA. Two new DOSXYZnrc sources for 4D Monte Carlo simulations of continuously variable beam configurations, with applications to RapidArc, VMAT, TomoTherapy and CyberKnife. Phys. Med. Biol. 2010; 55(16): 4431-4443.
[4]. ROGERS DWO, WALTERS B & KAWRAKOW I. BEAMnrc Users Manual. Ionizing Radiation Standards. National Research Council of Canada, May 2007.
[5]. KAWRAKOW I, ROGERS DWO & WALTERS BRB. Large efficiency improvements in BEAMnrc using directional bremsstrahlung splitting. Ionizing Radiation Standards National Research Council of Canada. Physics Dept, Carleton University, Ottawa K1S 5B6, 2004.
[6]. WESTERMARK M, ARNDT J, NILSSON B, BRAHME A. Comparative dosimetry in narrow high-energy photon beams. Phys Med Biol. 2000; 45(3): 685-702.
[7]. EKLUND K & AHNESJ OA. Modeling silicon diode energy response factors for use in therapeutic photon beams. Phys Med Biol. 2004; 54(20): 6135-6150.
[8]. YIN Z, HUGTENBURG RP & BEDDOE AH. Response corrections for solid-state detectors in megavoltage photon dosimetry. Phys Med Biol. 2004; 49(16): 3691-3702.
[9]. EKLUND K. Modeling Silicon diode dose response in radiotherapy fields using fluence pencil kernels. PhD thesis. Faculty of Medicine, Uppsala University. Uppsala, 2010. ISBN-978-91-554-7748-6.
[10]. SCOTT A, NAHUM A & FENWICK J. Monte Carlo modeling of small photon fi elds: quantifying the impact of focal spot size on source occlusion and output factors, and exploring miniphantom design for small-fi eld measurements. Medical Physics. 2009; 36(7): 3132-3144.
[11]. HEYDARIAN M, HOBAN PW & BEDDOE AH. A comparison of dosimetry techniques in stereotactic radiosurgery. Phys Med Biol. 1996; 41(1): 93-110.
[12]. ASPRADAKIS M, BYRNE J, PALMANS H, et. al. IPEM Report Number 103: Small field MV photon dosimetry. New York: IPEM, 2010. ISBN: 978-1-903613-45-0.
[13]. ROGERS DWO, WALTERS B & KAWRAKOW I. DOSXYZnrc Users Manual. Ionizing Radiation Standards. National Research Council of Canada, May 2007.