On the reliability of 3D gel dosimetry

7th International Conference on 3D Radiation Dosimetry

De Deene, Y.^1,2 ; Vandecasteele, J.^2

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

Department for Radiotherapy and Experimental Cancer Research, Ghent University Hospital, De Pintelaan 185, 9000 Gent, Belgium^2

关键词: Conformal radiotherapy;    Dose distributions;    Internal calibration;    Lack of confidences;    Overall accuracies;    Polymer gel dosimeter;    Polymer gel dosimetry;    Radiation oncologists;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/444/1/012015/pdf
DOI  :  10.1088/1742-6596/444/1/012015

来源: IOP

【 摘 要 】

Gel dosimetry has a unique role to play in safeguarding conformal radiotherapy treatments as it covers the whole treatment chain and provides the radiation oncologist with the integrated dose distribution in 3D. A major obstacle that has hindered the wider dissemination of polymer gel dosimetry in radiotherapy centres is the lack of confidence in the reliability of the measured dose. Discrepancies in dose response of small versus large polymer gel dosimeters have been reported and although several hypothesis for these discrepancies have been postulated, the actual contribution of these error sources to the overall inaccuracy of the dose maps has not been determined. Several gel dosimetry research groups have chosen to use an internal calibration of gel dosimeters. In this study, the inter-and intra-batch reproducibility of the current state-of-the-art 3D gel dosimeters has been assessed. It is demonstrated that with a carefully designed scanning set-up, the overall accuracy that can be obtained with an independent calibration is well within 5% of all pixels.