Do saccharide doped PAGAT dosimeters increase accuracy?

8th International Conference on 3D Radiation Dosimetry

Berndt, B.^1 ; Skyt, P.S.^1,2 ; Holloway, L.^3,5 ; Hill, R.^4 ; Sankar, A.^3 ; De Deene, Y.^1,6

Institute of Medical Physics, University of Sydney, Sydney, Australia^1

Department of Medical Physics, Aarhus University Hospital, Aarhus, Denmark^2

Liverpool Cancer Therapy Centre, Sydney, Australia^3

Chris o'Brien Lifehouse, Sydney, Australia^4

Macarthur Cancer Therapy Centre, Sydney, Australia^5

Department of Engineering, Macquarie University, Sydney, Australia^6

关键词: Dose sensitivity;    Dose uncertainties;    Gel dosimeter;    Polymer gels;    Response sensitivity;    Temperature sensitivity;    Temperature variation;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/573/1/012029/pdf
DOI  :  10.1088/1742-6596/573/1/012029

来源: IOP

【 摘 要 】

To improve the dosimetric accuracy of normoxic polyacrylamide gelatin (PAGAT) gel dosimeters, the addition of saccharides (glucose and sucrose) has been suggested. An increase in R2-response sensitivity upon irradiation will result in smaller uncertainties in the derived dose if all other uncertainties are conserved. However, temperature variations during the magnetic resonance scanning of polymer gels result in one of the highest contributions to dosimetric uncertainties. The purpose of this project was to study the dose sensitivity against the temperature sensitivity. The overall dose uncertainty of PAGAT gel dosimeters with different concentrations of saccharides (0, 10 and 20%) was investigated. For high concentrations of glucose or sucrose, a clear improvement of the dose sensitivity was observed. For doses up to 6 Gy, the overall dose uncertainty was reduced up to 0.3 Gy for all saccharide loaded gels compared to PAGAT gel. Higher concentrations of glucose and sucrose deteriorate the accuracy of PAGAT dosimeters for doses above 9 Gy.