Dose rate measurement of Leksell Gamma Knife Perfexion using a 3D printed plastic scintillation dosimeter

In recent years, 3D printing technology has received significant research attention. Additionally, 3D printing technology is being applied to study radiation dosimeters of various materials. In this study, a plastic scintillator for 3D printing was developed in a laboratory and used to manufacture a plastic scintillation dosimeter (PSD) with a shape identical to that of the ionization chamber PTW31010. The 16-mm beam of Gamma Knife (R) Perfexion (TM) was irradiated to derive the absorbed dose rates of the PSD and PTW31010; they were subsequently compared with the dose rates of the treatment plan. The differences in the dose rates of the Gamma Knife treatment plan and the absorbed dose rates of PTW31010 were within 0.87%. The difference between the dose rates of the Gamma Knife treatment plan and the absorbed dose rates of the PSD were within 4.1%. A linear fit of the absorbed dose rates of four shots involving different dose rates and irradiation angles yielded an adjusted R-square value exceeding 0.9999. A total of 10 repeated measurements were conducted for the same shot to confirm its reproducibility, with a relative error of 0.56%. (c) 2020 Korean Nuclear Society, Published by Elsevier Korea LLC. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).