CT number calibration audit in photon radiation therapy.
CT calibration
audit
photon radiation therapy
quality assurance
stoichiometric method
Journal
Medical physics
ISSN: 2473-4209
Titre abrégé: Med Phys
Pays: United States
ID NLM: 0425746
Informations de publication
Date de publication:
19 Dec 2023
19 Dec 2023
Historique:
revised:
29
06
2023
received:
03
01
2023
accepted:
26
11
2023
medline:
19
12
2023
pubmed:
19
12
2023
entrez:
19
12
2023
Statut:
aheadofprint
Résumé
Inadequate computed tomography (CT) number calibration curves affect dose calculation accuracy. Although CT number calibration curves registered in treatment planning systems (TPSs) should be consistent with human tissues, it is unclear whether adequate CT number calibration is performed because CT number calibration curves have not been assessed for various types of CT number calibration phantoms and TPSs. The purpose of this study was to investigate CT number calibration curves for mass density (ρ) and relative electron density (ρ A CT number calibration audit phantom was sent to 24 Japanese photon therapy institutes from the evaluating institute and scanned using their individual clinical CT scan protocols. The CT images of the audit phantom and institute-specific CT number calibration curves were submitted to the evaluating institute for analyzing the calibration curves registered in the TPSs at the participating institutes. The institute-specific CT number calibration curves were created using commercial phantom (Gammex, Gammex Inc., Middleton, WI, USA) or CIRS phantom (Computerized Imaging Reference Systems, Inc., Norfolk, VA, USA)). At the evaluating institute, theoretical CT number calibration curves were created using a stoichiometric CT number calibration method based on the CT image, and the institute-specific CT number calibration curves were compared with the theoretical calibration curve. Differences in ρ and ρ The mean ± standard deviation (SD) of Δρ Latent deviations between human tissues and TEMs were found by comparing the CT number calibration curves of the various institutes.
Sections du résumé
BACKGROUND
BACKGROUND
Inadequate computed tomography (CT) number calibration curves affect dose calculation accuracy. Although CT number calibration curves registered in treatment planning systems (TPSs) should be consistent with human tissues, it is unclear whether adequate CT number calibration is performed because CT number calibration curves have not been assessed for various types of CT number calibration phantoms and TPSs.
PURPOSE
OBJECTIVE
The purpose of this study was to investigate CT number calibration curves for mass density (ρ) and relative electron density (ρ
METHODS
METHODS
A CT number calibration audit phantom was sent to 24 Japanese photon therapy institutes from the evaluating institute and scanned using their individual clinical CT scan protocols. The CT images of the audit phantom and institute-specific CT number calibration curves were submitted to the evaluating institute for analyzing the calibration curves registered in the TPSs at the participating institutes. The institute-specific CT number calibration curves were created using commercial phantom (Gammex, Gammex Inc., Middleton, WI, USA) or CIRS phantom (Computerized Imaging Reference Systems, Inc., Norfolk, VA, USA)). At the evaluating institute, theoretical CT number calibration curves were created using a stoichiometric CT number calibration method based on the CT image, and the institute-specific CT number calibration curves were compared with the theoretical calibration curve. Differences in ρ and ρ
RESULTS
RESULTS
The mean ± standard deviation (SD) of Δρ
CONCLUSIONS
CONCLUSIONS
Latent deviations between human tissues and TEMs were found by comparing the CT number calibration curves of the various institutes.
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Subventions
Organisme : Japan Agency for Medical Research and Development (AMED)
ID : 2031526
Organisme : National Cancer Center Research and Development Fund
ID : 2020-J-3
Organisme : Japan Society for the Promotion of Science (JSPS)
ID : 19K12865
Organisme : Japan Society for the Promotion of Science (JSPS)
ID : 23K14869
Informations de copyright
© 2023 The Authors. Medical Physics published by Wiley Periodicals LLC on behalf of American Association of Physicists in Medicine.
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