Can a commercial gel dosimetry system be used to verify stereotactic spinal radiotherapy treatment dose distributions?

9th International Conference on 3D Radiation Dosimetry

Kairn, T.^1,2 ; Asena, A.^2 ; Crowe, S.B.^2,3 ; Livingstone, A.^3 ; Papworth, D.^1 ; Smith, S.^2 ; Sutherland, B.^1 ; Sylvander, S.^3 ; Franich, R.D.^4 ; Trapp, J.V.^2

Genesis Cancer Care Queensland, Brisbane, Australia^1

School of Chemistry, Physics, and Mechanical Engineering, Queensland University of Technology, Brisbane, Australia^2

Royal Brisbane and Women's Hospital, Brisbane, Australia^3

School of Science, RMIT University, Melbourne, Australia^4

关键词: Calibration measurements;    Dose distributions;    Film measurement;    Gel measurement;    Lower resolution;    Radiotherapy treatment;    Treatment planning systems;    Varian medical systems;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/847/1/012071/pdf
DOI  :  10.1088/1742-6596/847/1/012071

来源: IOP

【 摘 要 】

This study investigated the use of the TruView xylenol-orange-based gel and VISTA optical CT scanner (both by Modus Medical Inc, London, Canada), for use in verifying the accuracy of planned dose distributions for hypo-fractionated (stereotactic) vertebral treatments. Gel measurements were carried out using three stereotactic vertebral treatments and compared with planned doses calculated using the Eclipse treatment planning system (Varian Medical Systems, Palo Alto, USA) as well as with film measurements made using Gafchromic EBT3 film (Ashland Inc, Covington, USA), to investigate the accuracy of the gel system. The gel was calibrated with reference to a moderate-dose gradient region in one of the gel samples. Generally, the gel measurements were able to approximate the close agreement between the doses calculated by the treatment planning system and the doses measured using film (which agreed with each other within 2%), despite lower resolution and bit depth. Poorer agreement was observed when the dose delivered to the gel exceeded the range of doses delivered in the calibration region. This commercial gel dosimetry system may be used to verify hypo-fractionated treatments of vertebral targets, although separate gel calibration measurements are recommended.