Dosimetric characteristics of 6 MV photons from TrueBeam STx medical linear accelerator: simulation and experimental data
Main Article Content
Abstract
A TrueBeam STx is one of the most technologically advanced linear accelerators for
radiotherapy and radiosurgery. The Monte Carlo simulation widely used in many applications in various fields such as nuclear physics, astrophysics, particle physics, and medicine. The Geant4/GATE Monte Carlo toolkit is developed for the simulation in imaging diagnostics, nuclear medicine, radiotherapy, and radiation biology to more accurately predict beam radiation dosimetry. In this work, we present the simulation results of the dosimetric characteristics of a 6 MV photon beam of TrueBeam STx medical LINAC using Monte Carlo Geant4/GATE. The percentage depth dose (PDD), central axis depth dose (Profile) have been simulated and compared with those measured in a water phantom for field sizes 10×10 cm2 via the gamma-index method. These results will permit to check calculation data given by the treatment planning system.
Article Details
Keywords
Geant4/GATE, Radiotherapy, TrueBeam STx, Phase Space file, PDD, Profile
References
[2]. N. Reynaert et al., “Monte Carlo treatment planning for photon and electron beams,” Radiation Physics and Chemistry 76, 643–686, 2007.
[3]. E. Spezi and G. Lewis, “An overview of Monte Carlo treatment planning for radiotherapy,” Radiation Protection Dosimetry 131, 123–129, 2008.
[4]. O. Chibani and C.-M. Ma, “On the discrepancies between Monte Carlo dose calculations and measurements for the 18 MV Varian photon beam,” Med. Phys. 34, 1206–1216, 2007.
[5]. M. Constantin et al., “Modeling the TrueBeam linac using a CAD to Geant4 geometry implementation: Dose and IAEA-compliant Phase Space calculations,” Medical Physics 38, 4018–4024, 2011.
[6]. C. Glide-Hurst et al., “Commissioning of the Varian TrueBeam linear accelerator: A multi-institutional study,” Medical Physics 40, 031719, 2013.
[7]. G. P. Beyer, “Commissioning measurements for photon beam data on three TrueBeam linear accelerators, and comparison with Trilogy and Clinac 2100 linear accelerators,” J. Appl. Clin. Med. Phys. 14, 273–288, 2013.
[8]. Rodrigues et al., “A Monte Carlo simulation framework for electron beam dose calculations using Varian Phase Space files for TrueBeam Linacs”, Medical Physics 42, 2389-2403, 2015.
[9]. S. Agostinelli et al., “Geant4—a simulation toolkit”, Nucl. Instr. and Meth. in Phys. Res. A 506, 250, 2003.
[10]. J. Allison et al., “Recent developments in Geant4”, Nuclear Instruments and Methods in Physics Research A 835, 186, 2016.
[11]. L. Grevillot et al., “Simulation of a 6 MV Elekta precise linac photon beam using GATE/GEANT4, Physics in Medicine & Biology 56 903–918, 2011.
[12]. J. EL Bakkali et al., “Validation of Monte-Carlo Geant4 code for Saturne 43 LINAC”, Int. J. Innov. Appl. Stud. 4, 424–436, 2013.
[13]. S. Didi et al., “Simulation of the 6 MV Elekta synergy platform linac photon beam using Geant4 application for tomographic emission”, Medical Physics 40,136–143, 2015.
[14]. Wijesooriya et al., “Verification of the TrueBeam Head Shielding Model in Varian VirtuaLinac via Out-of-field Doses”, Medical Physics 46(2), 877-884, 2019.
[15]. R. Shende et al., “Commissioning of TrueBeam TM Medical Linear Accelerator: Quantitative and Qualitative Dosimetric Analysis and Comparison of Flattening Filter (FF) and Flattening Filter Free (FFF) Beam,” no. February, pp. 51–69, 2016.
[16]. C. Glide-Hurst et al., “Commissioning of the Varian TrueBeam linear accelerator: a multi-institutional study.,” Med. Phys., vol. 40, no. 3, p. 31719, 2013.
[17]. G. P. Beyer, “Commissioning measurements for photon beam data on three TrueBeam linear accelerators, and comparison with Trilogy and Clinac 2100 linear accelerators.,” J. Appl. Clin. Med. Phys., vol. 14, no. 1, p. 4077, 2013.
[18]. International Atomic Energy Agency Technical Report IAEA-NDS-0484: “Phase-Space Database for External Beam Radiotherapy”, IAEA Headquarters, Vienna, Austria, 2006.
[19]. “TrueBeam Monte Carlo Data Package” – Confidential document for TrueBeam STx users, version 1.1, 2014.
[20]. https://www.iba-dosimetry.com – accessed: March 2019.
[21]. P. R. Almond and P. J. Biggs, “AAPM” TG-51 protocol for clinical reference dosimetry of high-energy photon and electron beams,” no. September, pp. 1847–1870, 1999.
[22]. R. J. Watts et al., “Accelerator beam data commissioning equipment and procedures: Report of the TG-106 of the Therapy Physics Committee of the AAPM,” pp. 4186–4215, 2008.
[23]. S. Jan et al., “Gate: a simulation toolkit for PET and SPECT”, Physics in Medicine & Biology 49(19), 4543-61, 2004.
[24]. S. Jan et al, “GATE V6: a major enhancement of the GATE simulation platform enabling modelling of CT and Radiotherapy” Physics in Medicine & Biology 56(4), 881-901, 2011.
[25]. L. Grevillot et al., “GATE as a GEANT4-based Monte Carlo platform for the evaluation of proton pencil beam scanning treatment plans”, Phys. in Med. & Bio. 57(13), 4223-44, 2012.
[26]. www.opengatecollaboration.org – accessed: March 2019.
[27]. E. Poon and F. Verhaegen, “Accuracy of the photon and electron physics in Geant4 for radiotherapy applications”, Medical Physics 32, 1696–711, 2005.
[28]. P. Arce, JI lagares, “CPU time optimization and precise adjustment of the Geant4 physics parameters for a VARIAN 2100 C/D gamma radiotherapy linear accelerator simulation using GAMOS”, Physics in Medicine & Biology 63(3), 035007, 2018.
[29]. D. A. Low et al., “A technique for the quantitative evaluation of dose distributions”, Medical Physics 25(5), 656-661, 1998.
[30]. Graves, Y.J., Jia, X. & Jiang, “Effect of statistical fluctuation in Monte Carlo based photon beam dose calculation on gamma index evaluation”, Physics in Medicine and Biology 58(6): 1839-1854, 2013.
[31]. Saidi, P., Tenreiro, C. & Sadeghi, “Variance Reduction of Monte Carlo Simulation in Nuclear Engineering Field”, Rijeka, Croatia: INTECH Open Access Publisher: Theory and Applications of Monte Carlo Simulations, 2013.