Empirical quenching correction in radiochromic silicone-based three-dimensional dosimetry of spot-scanning proton therapy.
3D dosimetry
Dosimeter calibration
Proton therapy
Quenching
Journal
Physics and imaging in radiation oncology
ISSN: 2405-6316
Titre abrégé: Phys Imaging Radiat Oncol
Pays: Netherlands
ID NLM: 101704276
Informations de publication
Date de publication:
Apr 2021
Apr 2021
Historique:
received:
09
07
2020
revised:
25
03
2021
accepted:
27
03
2021
entrez:
14
7
2021
pubmed:
15
7
2021
medline:
15
7
2021
Statut:
epublish
Résumé
Three-dimensional dosimetry of proton therapy (PT) with chemical dosimeters is challenged by signal quenching, which is a lower dose-response in regions with high ionization density due to high linear-energy-transfer (LET) and dose-rate. This study aimed to assess the viability of an empirical correction model for 3D radiochromic silicone-based dosimeters irradiated with spot-scanning PT, by parametrizing its LET and dose-rate dependency. Ten cylindrical radiochromic dosimeters (Ø50 and Ø75 mm) were produced in-house, and irradiated with different spot-scanning proton beam configurations and machine-set dose rates ranging from 56 to 145 Gy/min. Beams with incident energies of 75, 95 and 120 MeV, a spread-out Bragg peak and a plan optimized to an irregular target volume were included. Five of the dosimeters, irradiated with 120 MeV beams, were used to estimate the quenching correction factors. Monte Carlo simulations were used to obtain dose and dose-averaged-LET (LET Gamma-pass-rates of the corrected measurements were >94% using a 3%-3 mm gamma analysis and >88% using 2%-2 mm, with a dose deviation of <5.6 ± 1.8%. Larger dosimeters showed a 20% systematic increase in dose-response, but the same quenching in signal when compared to the smaller dosimeters. The quenching correction model was valid for different dosimeter sizes to obtain relative dosimetric maps of complex dose distributions in PT.
Sections du résumé
BACKGROUND AND PURPOSE
OBJECTIVE
Three-dimensional dosimetry of proton therapy (PT) with chemical dosimeters is challenged by signal quenching, which is a lower dose-response in regions with high ionization density due to high linear-energy-transfer (LET) and dose-rate. This study aimed to assess the viability of an empirical correction model for 3D radiochromic silicone-based dosimeters irradiated with spot-scanning PT, by parametrizing its LET and dose-rate dependency.
MATERIALS AND METHODS
METHODS
Ten cylindrical radiochromic dosimeters (Ø50 and Ø75 mm) were produced in-house, and irradiated with different spot-scanning proton beam configurations and machine-set dose rates ranging from 56 to 145 Gy/min. Beams with incident energies of 75, 95 and 120 MeV, a spread-out Bragg peak and a plan optimized to an irregular target volume were included. Five of the dosimeters, irradiated with 120 MeV beams, were used to estimate the quenching correction factors. Monte Carlo simulations were used to obtain dose and dose-averaged-LET (LET
RESULTS
RESULTS
Gamma-pass-rates of the corrected measurements were >94% using a 3%-3 mm gamma analysis and >88% using 2%-2 mm, with a dose deviation of <5.6 ± 1.8%. Larger dosimeters showed a 20% systematic increase in dose-response, but the same quenching in signal when compared to the smaller dosimeters.
CONCLUSION
CONCLUSIONS
The quenching correction model was valid for different dosimeter sizes to obtain relative dosimetric maps of complex dose distributions in PT.
Identifiants
pubmed: 34258402
doi: 10.1016/j.phro.2021.03.006
pii: S2405-6316(21)00020-8
pmc: PMC8254200
doi:
Types de publication
Journal Article
Langues
eng
Pagination
11-18Informations de copyright
© 2021 The Authors.
Déclaration de conflit d'intérêts
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Références
Phys Med Biol. 2011 Feb 7;56(3):627-51
pubmed: 21220844
Phys Imaging Radiat Oncol. 2020 Nov 20;16:134-137
pubmed: 33458356
Med Phys. 2020 Jun;47(5):2289-2299
pubmed: 32166764
Nucl Instrum Methods Phys Res B. 1996 Feb;107(1-4):287-91
pubmed: 11540424
Phys Med Biol. 2013 Jan 21;58(2):261-73
pubmed: 23257200
Phys Med Biol. 2018 Nov 07;63(21):215028
pubmed: 30403194
Phys Med Biol. 2019 Mar 07;64(5):055015
pubmed: 30673655
Phys Med Biol. 2010 May 21;55(10):2819-40
pubmed: 20413828
Phys Med Biol. 2011 Aug 21;56(16):5203-19
pubmed: 21791731
IEEE Trans Med Imaging. 2010 Jan;29(1):196-205
pubmed: 19923044
Phys Med Biol. 2010 Mar 7;55(5):R1-63
pubmed: 20150687
Phys Med Biol. 2004 Sep 7;49(17):3847-55
pubmed: 15470909
Med Dosim. 2013 Winter;38(4):390-4
pubmed: 23916884
Phys Med Biol. 2011 Oct 21;56(20):6677-91
pubmed: 21965268
Med Phys. 2012 Nov;39(11):6818-37
pubmed: 23127075
Med Phys. 2002 Apr;29(4):569-77
pubmed: 11991129
Med Phys. 2016 Jun;43(6):2780-2784
pubmed: 27277025
Phys Med Biol. 2017 Feb 21;62(4):N73-N89
pubmed: 28134130
Phys Med Biol. 2019 Apr 29;64(9):095018
pubmed: 30909170
Phys Med Biol. 2014 Aug 7;59(15):4295-310
pubmed: 25029434
Phys Med Biol. 2015 Feb 21;60(4):1543-63
pubmed: 25615261
Phys Med Biol. 2015 Jul 21;60(14):5557-70
pubmed: 26134268
Phys Med Biol. 2017 Jun 14;62(14):5612-5622
pubmed: 28467323
Med Phys. 2020 Apr;47(4):1545-1557
pubmed: 31945191
Acta Oncol. 2013 Oct;52(7):1445-50
pubmed: 23957684
Med Phys. 2013 Dec;40(12):121719
pubmed: 24320505
Med Phys. 2012 Dec;39(12):7232-6
pubmed: 23231274
J Appl Clin Med Phys. 2015 Nov 08;16(6):151–163
pubmed: 26699567