Calculation of gel dose after external radiation therapy using optical CT

Authors

Abstract

In this study, the MAGIC- f polymer gel was used to determine the absorbed dose by external radiation therapy. The MAGIC- f gel was made under normal pressure and temperature conditions and irradiated with a Siemens 6MV linear accelerator at 10 × 10 cm2 and at a depth of 10 cm. While simulating the head of the accelerator unit by the Monte Carlo method with BEAMnrc code, the percentage depth dose (PDD) and dose profile is calculated in different fields of 4 × 4, 6 × 6 and 10×10 cm2 with DOSXYZnrc code. Also after gel irradiation, the gel readings were performed by CT optical apparatus and made at the Nuclear Laboratory of Mazandaran University. The results of the experimental and simulation results show that the PDD diagram and dose profile are in good agreement with the maximum error rate of 2% and these results confirm the accuracy and efficiency of the OCT device designed for dose reading in radiation therapy.
 

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