Radiotherapy Measurements Using Fricke Gel Dosimeter

Abstract

HE RADIOTHERAPY is mainly used in cancer treatment. The treatment machines are divided into two types, one is depending on natural sources (e.g cobalt 60 machine) which delivers gamma ray and the other is depending on artificial source such as linear accelerator machine (Linac), they both deliver electron and X-ray with different energies. To calculate treatment dose or to setup a radiotherapy plan for a patient with suitable energy, some parameters must be measured to check the quality and the quantity of this energy. In present study, dosimetric parameters, such as calibration curve, open and wedged beam profiles and total scatter factors, are evaluated for two mega voltage photons "X-ray" (6 & 15 MV) and two electrons (6 & 15 MeV) beam energies using a chemical dosimeters such as Fricke Xylenol Gel dosimeter (FXG). The measurements are compared with other dosimeters such as ionization chambers and daily QA machine. The aim of this work is to evaluate the FXG to be used in measuring these parameters and acts as alternative dosimeter used in daily quality assurance checks. The results show that the differences of these parameters between the standard dosimeters (Ionization chambers and daily QA machine) are not more than 3%.