Dosimetric Characterizations of Megavoltage Therapeutic Photon Beam
Md. Abdullah Al Mashud *
Department of Electrical and Electronic Engineering, Islamic University, Kushtia-7003, Bangladesh.
M. Jahangir Alam
Medical Physics Division, Department of Radiation Oncology, Ahsania Mission Cancer and General Hospital, Uttara, Dhaka, Bangladesh.
*Author to whom correspondence should be addressed.
Abstract
This paper presents the dosimetric parameters characterizations of a megavoltage therapeutic photon beam. The main focus of this study is to investigate and analyze the parameters of percentage depth dose (PDD) and tissue maximum ratio (TMR) due to the importance of treatment system. The depth dose characteristics of 6MV photon beam for different field sizes in water phantom has been measured, analyzed and found a robustness results. The results revealed that the depth dose variation from 0.067% to 1.812% and the TMR values varies from 0.501% to 2.111%. It seems the measured dosimetric quantities are clinically relevant for different field sizes and depths.
Keywords: PDD, TMR, accuracy, LINAC, photon beam