Hostname: page-component-78c5997874-8bhkd Total loading time: 0 Render date: 2024-11-20T03:25:02.875Z Has data issue: false hasContentIssue false

Monte Carlo simulation of electron modes of a Siemens Primus linac (8, 12 and 14 MeV)

Published online by Cambridge University Press:  01 May 2013

Mohammad Taghi Bahreyni Toossi
Affiliation:
Medical Physics Research Center, Medical Physics Department, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
Mahdi Ghorbani*
Affiliation:
Medical Physics Research Center, Medical Physics Department, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
Fateme Akbari
Affiliation:
Medical Physics Department, Reza Radiation Oncology Center, Mashhad, Iran
Leila Sobhkhiz Sabet
Affiliation:
Medical Physics Research Center, Medical Physics Department, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
Mohammad Mehrpouyan
Affiliation:
Nutrition and Biochemistry Department, Faculty of Medicine, Sabzevar University of Medical Sciences, Sabzevar, Iran
*
Correspondence to: Dr Mahdi Ghorbani, Medical Physics Department, Faculty of Medicine, Mashhad University of Medical Sciences, Pardis-e-Daneshgah, Vakil Abad Blvd., Mashhad 9177948564, Iran. Tel: +98 511 8002316. Fax: +98 511 8002320. E-mail: [email protected]

Abstract

Background

Electron mode is used for treatment of superficial tumours in linac-based radiotherapy.

Purpose

The aim of present study is simulation of 8, 12 and 14 MeV electrons from a Siemens Primus linac using MCNPX Monte Carlo (MC) code and verification of the results based on comparison of the results with the measured data.

Materials and methods

Electron mode for 8, 12 and 14 MeV electron energies of a Siemens Primus linac was simulated using MCNPX MC code. Percent depth dose (PDD) data for 10 × 10, 15 × 15 and 25 × 25 cm2 applicators obtained from MC simulations were compared with the corresponding measured data.

Results

Gamma index values were less than unity in most of points for all the above-mentioned energies and applicators. However, for 25 × 25 cm2 applicator in 8 MeV energy, 10 × 10 cm2 applicator and 15 × 15 cm2 applicator in 14 MeV energy, there were four data points with gamma indices higher than unity. However among these data points, there are a number of cases with relatively large value of gamma index, these cases are positioned on the bremsstrahlung tail of the PDD curve which is not normally used in treatment planning.

Conclusion

There was good agreement between the results of MC simulations developed in this study and the measured values. The obtained simulation programmes can be used in dosimetry of electron mode of Siemens Primus linac in the cases in which it is not easily feasible to perform experimental in-phantom measurements.

Type
Original Articles
Copyright
Copyright © Cambridge University Press 2013 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1.Vega-Carrillo, H, Ortiz-Hernandez, A, Hernandez-Davila, V, Berenice Hernandez-Almaraz, B, Rivera Montalvo, T. H*(10) and neutron spectra around linacs. J Radioanal Nucl Chem 2009; 283: 537540.CrossRefGoogle Scholar
2.Jabbari, N, Hashemi-Malayeri, B. Monte Carlo modeling of electron beams from a NEPTUN 10PC medical linear accelerator. Nukleonika 2009; 54: 233238.Google Scholar
3.Rogers, D W O, Faddegon, B A, Ding, G X, Ma, C M, We, J, Mackie, T R. BEAM: a Monte Carlo code to simulate radiotherapy treatment units. Med Phys 1995; 22: 503524.CrossRefGoogle Scholar
4.Sardari, D, Maleki, R, Samavat, H, Esmaeeli, A. Measurement of depth-dose of linear accelerator and simulation by use of Geant4 computer code. Rep Pract Oncol Radiother 2010; 15: 6468.CrossRefGoogle ScholarPubMed
5.Jiang, S B, Kapur, A, Ma, C M. Electron beam modeling and commissioning for Monte Carlo treatment planning. Med Phys 2000; 27: 180191.CrossRefGoogle ScholarPubMed
6.Pemler, P, Besserer, J, Schneider, U, Neuenschwander, H. Evaluation of a commercial electron treatment planning system based on Monte Carlo techniques (eMC). Z Med Phys 2006; 16: 313329.CrossRefGoogle ScholarPubMed
7.Mika, S, Christ, G. Experimental validation of a Monte Carlo-based treatment-planning system for electron beams. Strahlenther Onkol 2007; 183 (3): 150156.CrossRefGoogle ScholarPubMed
8.Schiapparelli, P, Zefiro, D, Taccini, G. Dosimetric verification of a commercial Monte Carlo treatment planning system (VMC++) for a 9 MeV electron beam. Med Phys 2009; 36: 17591767.CrossRefGoogle ScholarPubMed
9.Ding, G X, Cygler, J E, Yu, C W, Kalach, N I, Daskalov, G. A comparison of electron beam dose calculation accuracy between treatment planning systems using either a pencil beam or a Monte Carlo algorithm. Int J Radiat Oncol Biol Phys 2005; 63: 622633.CrossRefGoogle ScholarPubMed
10.Nedaie, H, Mosleh-Shirazi, M, Shariary, M, Gharaati, H, Allahverdi, M. Monte Carlo study of electron dose distributions produced by the ELEKTA Precise linear accelerator. Rep Pract Oncol and Radiother 2006; 11: 287292.CrossRefGoogle Scholar
11.Darko, L, Radovan, D, Stankovi, S. Comparison of measured and Monte Carlo calculated electron beam central axis depth dose in water. Arch Oncol 2001; 9: 8387.Google Scholar
12.Verhaegen, F, Mubata, C, Pettingell, Jet al. Monte Carlo calculation of output factors for circular, rectangular, and square fields of electron accelerators (6–20 MeV). Med Phys 2001; 28: 938949.CrossRefGoogle ScholarPubMed
13.Sempau, J, Sánchez-Reyes, A, Salvat, F, Tahar, H, Jiang, S, Fernández-Varea, J. Monte Carlo simulation of electron beams from an accelerator head using PENELOPE. Phys Med Biol 2001; 46: 11631186.CrossRefGoogle ScholarPubMed
14.Waters, LS. MCNPX User's Manual, Version 2.4.0. Report LA-CP-02-408 2002; Los Alamos National Laboratory.Google Scholar