Broadhead B, Noble C, Ramachandran P. A direct comparison of the optically stimulated luminescent properties of BeO and Al
2O
3 for clinical in-vivo dosimetry.
Phys Eng Sci Med 2022;
45:859-866. [PMID:
35816274 PMCID:
PMC9448691 DOI:
10.1007/s13246-022-01155-x]
[Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 06/15/2022] [Indexed: 11/25/2022]
Abstract
Optically stimulated luminescence dosimetry is a relatively recent field of in-vivo dosimetry in clinical radiotherapy, developing over the last 20 years. As a pilot study, this paper presents a direct comparison between the sensitivity variance with use, stability of measurement and linearity of the current clinical standard Al2O3:C and a potential alternative, beryllium oxide. A set of ten optically stimulated luminescence dosimeters (OSLD), including five of each type, were used simultaneously and irradiated on a Versa HD linear accelerator. Having similar sensitivity, while Al2O3:C showed a relatively stable signal response from initial use, BeO was found to have a higher response to the same dose. However, BeO displayed a strong exponential decline from initial signal response following a model of [Formula: see text], reaching stability after approximately 10 irradiation cycles. BeO was shown to have potentially higher accuracy than Al2O3:C, with less variation between individual doses. Both OSLD showed good linearity between 0.2-5.0 Gy. Between these bounds, Al2O3:C demonstrated a strong linear response following the trend [Formula: see text], however beyond this showed deviation from linearity, resulting in a measured dose of [Formula: see text] Gy at 10.0 Gy dose delivery. BeO showed strong linearity across the full examined range of 0.2-10.0 Gy with following a model of [Formula: see text] Gy with a recorded dose at 10.0 Gy delivery as [Formula: see text] Gy. In conclusion, BeO does show large variance in sensitivity between individual OSLD and a considerable initial variance and decline in dose-response, however after pre-conditioning and individual normalisation to offset OSLD specific sensitivity BeO provides not only a viable alternative to Al2O3:C, but potentially provide higher accuracy, precision and reproducibility for in-vivo dosimetry.
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