Comparison of Photon Contamination between Lead free and Flexible Internal Shield and Lead for 6 and 9 MeV Electron Beams of Varian 2100 C/D

Document Type : Original Article


1 Department of Medical Physics and Radiotherapy, Ahvaz University of Medical Sciences, Ahvaz, Iran

2 Expert Radiotherapy Department of Golestan Hospital in Ahvaz, Iran


Background and Objective: In the recent decades the Monte Carlo simulation in the field of radiation therapy has been used a lot. In this study photon contamination of Lead free and flexible internal shield was investigated in the electron field.
Subjects and Methods:To evaluate photon contaminationthat caused by this new material in the electron field by Mont Carlo study. Varian 2100 C/D was validated within measurement and then by given energy spectrum shield thickness and photon contamination were obtained and compared to those of lead.
Results:The results show that this material required 1.2 times thickness of those leadfor providing protection. In addition, it causes photon contamination approximately equal those of lead for energy 6 and 9 MeV.
Conclusions: It can be concluded that thickness of  specific combination (70% W, 18.61% Ni, 11/39% c) which has equal transmission same as lead caused photon contamination equal those of Lead that it can be acceptable under clinical condition.
Please cite this paper as:
JavadTahmasebiBirgani M, Zabihzadeh M, Aliakbari S, Abdalvand N, Shams A.Comparison of Photon Contamination between Lead free and Flexible Internal Shield and Lead for 6 and 9 MeV Electron Beams of Varian 2100 C/D.JundishapurSci Med J 2017;16(1):35-44.


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