Journal of Medical Physics
ORIGINAL ARTICLE
Year
: 2018  |  Volume : 43  |  Issue : 3  |  Page : 162--167

Comparison of measured and Monte Carlo calculated dose distributions from indigenously developed 6 MV flattening filter free medical linear accelerator


Bibekananda Mishra1, Subhalaxmi Mishra2, T Palani Selvam2, ST Chavan3, SN Pethe3 
1 Radiological Safety Division, Atomic Energy Regulatory Board; Homi Bhabha National Institute, Mumbai, Maharashtra, India
2 Homi Bhabha National Institute; Radiological Physics and Advisory Division, Health, Safety and Environment Group, Bhabha Atomic Research Centre, Mumbai, Maharashtra, India
3 Medical Electronics Division-1, Society for Applied Microwave Electronics Engineering and Research, Mumbai, Maharashtra, India

Correspondence Address:
Mr. Bibekananda Mishra
Radiological Safety Division, Atomic Energy Regulatory Board, Mumbai - 400 094, Maharashtra
India

Purpose: Monte Carlo simulation was carried out for a 6 MV flattening filter-free (FFF) indigenously developed linear accelerator (linac) using the BEAMnrc user-code of the EGSnrc code system. The model was benchmarked against the measurements. A Gaussian distributed electron beam of kinetic energy 6.2 MeV with full-width half maximum of 1 mm was used in this study. Methods: The simulation of indigenously developed linac unit has been carried out by using the Monte Carlo-based BEAMnrc user-code of the EGSnrc code system. Using the simulated model, depth and lateral dose profiles were studied using the DOSXYZnrc user-code. The calculated dose data were compared against the measurements using an RFA dosimertic system made by PTW, Germany (water tank MP3-M and 0.125 cm3 ion chamber). Results: The BEAMDP code was used to analyze photon fluence spectra, mean energy distribution, and electron contamination fluence spectra. Percentage depth dose (PDD) and beam profiles (along both X and Y directions) were calculated for the field sizes 5 cm × 5 cm - 25 cm × 25 cm. The dose difference between the calculated and measured PDD and profile values were under 1%, except for the penumbra region where the maximum deviation was found to be around 3%. Conclusions: A Monte Carlo model of indigenous FFF linac (6 MV) has been developed and benchmarked against the measured data.


How to cite this article:
Mishra B, Mishra S, Selvam T P, Chavan S T, Pethe S N. Comparison of measured and Monte Carlo calculated dose distributions from indigenously developed 6 MV flattening filter free medical linear accelerator.J Med Phys 2018;43:162-167


How to cite this URL:
Mishra B, Mishra S, Selvam T P, Chavan S T, Pethe S N. Comparison of measured and Monte Carlo calculated dose distributions from indigenously developed 6 MV flattening filter free medical linear accelerator. J Med Phys [serial online] 2018 [cited 2018 Dec 15 ];43:162-167
Available from: http://www.jmp.org.in/article.asp?issn=0971-6203;year=2018;volume=43;issue=3;spage=162;epage=167;aulast=Mishra;type=0