Characterization of a reusable PRESAGE? 3D dosimeter

[摘要] This study investigates a reusable PRESAGE® 3D dosimeter (Presage-RU), which would improve cost-effectiveness and facilitate wider implementation of comprehensive, high resolution 3D dosimetry. Small (1x1x4.5 cm) and large (8 cm diameter, 4.5 cm length) sample dosimeters were irradiated multiple times to characterize dose response (i.e. radiation-induced change in optical density (ΔOD)), optical clearing rate, and dose distribution stability. Presage- RU exhibited an initial dose response sensitivity of 0.0119 ΔOD/(cm-Gy), a reduction in response with subsequent irradiations, and a small, permanent ΔOD (∼1-6% of initial signal) following each irradiation. Dosimeters optically cleared at an exponential rate (average T1/224.8±3.6 h), and were effectively cleared after ∼5-8 days. 3D gamma analysis (3%/3mm, 10% dose threshold) of a 4-field box plan applied to the large dosimeter showed good agreement following initial irradiation (96.6% passing), but a reduction in passing rate (89.1% passing) with subsequent irradiation. Further study is warranted to fully assess and quantify the performance of Presage-RU for repeat irradiations.

[发布机构] Medical Physics Graduate Program, Duke University, Durham; NC, United States^1;Duke University Medical Center, Durham; NC, United States^2;Rider University, Lawerenceville; NJ, United States^3;Heuris Pharma, LLC, 412 Sunset Rd., Skillman; NJ; 08558, United States^4

[关键词] 3d dosimeters;Dose distributions;Dose response;Exponential rates;Gamma analysis;High resolution;Optical clearing;Radiation-induced