The Experimental Assessment Of Build Up Factor And Attenuation Coefficient Of Brass Compensator Applied In Intensity-Modulated Radiation Therapy (Imrt) For 6mv Photon Beam
- Author:
Elnaz BALVASI
1
;
Peyman HEJAZI
;
Abbas HAGHPARAST
;
Raheb GHORBANI
;
Zaker SALEHI
Author Information
1. Department of Medical Physics, Semnan University of Medical Sciences, Semnan, Iran
- Publication Type:Original article
- Keywords:
Intensity Modulated Radiation Therapy;
Compensators;
Brass;
Effective Attenuation Coefficient;
Build up Fact
- From:Journal of University of Malaya Medical Centre
2017;20(2):26-30
- CountryMalaysia
- Language:English
-
Abstract:
Introduction: Recent compensators are commonly applied in IMRT. The precise properties of applied compensators such as thickness, attenuation coefficient and build up factor are intensively important for IMRT calculations. Method: The brass compensator used for 6 MV photon beam was studied to estimate the relative effect of thickness and field size on IMRT calculations. Various field size together with several compensator thicknesses were examined. Result: The average reduction of effective attenuation coefficient (EAC), for the fields of 10×10 cm2 to 20×20 cm2, was 9.94%. By increasing the field size, EAC was decreased. The major reduction of EAC due to increasing field size was found to be 9.62%. The build up factor was increased by 2% to 21.8% respect to field size and compensator thickness. Also, the build up factor was increased by adding up the thickness. The rate of changes ranged from 24% to 48 %.Conclusion: The compensator thickness and field size are significantly important to calculate the effective attenuation coefficient and build up facto
