Sensitivity of radio-photoluminescence glass dosimeters to accumulated doses

PLoS One. 2020 Dec 3;15(12):e0234829. doi: 10.1371/journal.pone.0234829. eCollection 2020.

Abstract

Background: This study investigated the effect of accumulated doses on radio-photoluminescence glass dosimeters (RPLGDs) from measurements involving mega-voltage photons.

Methods: Forty-five commercially available RPLGDs were irradiated to estimate their dose responses. Photon beams of 6, 10, and 15 MV were irradiated onto the RPLGDs inside a phantom, which were divided into five groups with different doses and energies. Groups 1 and 2 were irradiated at 1, 5, 10, 50, and 100 Gy in a sequential manner; Group 3 was irradiated 10 times with a dose of 10 Gy; and Groups 4 and 5 followed the same method as that of Group 3, but with doses of 50 Gy and 100 Gy, respectively. Each device was subjected to a measurement reading procedure each time irradiation.

Results: For the annealed Group 1, RPLGD exhibited a linearity response with variance within 5%. For the non-annealed Group 2, readings demonstrated hyperlinearity at 6 MV and 10 MV, and linearity at 15 MV. Following the 100 Gy irradiation, the readings for Group 2 were 118.7 ± 1.9%, 112.2 ± 2.7%, and 101.5 ± 2.3% at 6, 10, and 15 MV, respectively. For Groups 3, 4, and 5, the responsiveness of the RPLGDs gradually decreased as the number of repeated irradiations increased. The percentage readings for the 10th beam irradiation with respect to the readings for the primary beam irradiation were 84.6 ± 1.9%, 87.5 ± 2.4%, and 93.0 ± 3.0% at 6 MV, 10 MV, and 15 MV, respectively.

Conclusions: The non-annealed RPLGD response to dose was hyperlinear for the 6 MV and 10 MV photon beams but not for the 15 MV photon beam. Additionally, the annealed RPLGD exhibited a fading phenomenon when the measurement was repeated several times and demonstrated a relatively large fading effect at low energies than at high energies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Glass
  • Phantoms, Imaging
  • Photons
  • Radiation Dosage
  • Radiation Dosimeters*
  • Radiotherapy Dosage
  • Sensitivity and Specificity

Grants and funding

This work was supported by the National Cancer Center Grant (NCC-2010140-1), the general researcher program (NRF- 2018R1D1A1B07050217) and the nuclear safety research program (No. 2003013-0120-CG100) through the Korea Foundation of Nuclear Safety (KOFONS), using the financial resource granted by the Nuclear Safety and Security Commission (NSSC), Republic of Korea. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. None of authors received a salary from any of funders.