Accuracy of Dose Calibrators for 68Ga PET Imaging: Unexpected Findings in a Multicenter Clinical Pretrial Assessment.
J Nucl Med
; 59(4): 636-638, 2018 04.
Article
em En
| MEDLINE
| ID: mdl-29326354
ABSTRACT
We report the discovery of a systematic miscalibration during the work-up process for site validation of a multicenter clinical PET imaging trial using 68Ga, which manifested as a consistent and reproducible underestimation in the quantitative accuracy (assessed by SUV) of a range of PET systems from different manufacturers at several different facilities around Australia. Methods:
Sites were asked to follow a strict preparation protocol to create a radioactive phantom with 68Ga to be imaged using a standard clinical protocol before commencing imaging in the trial. All sites had routinely used 68Ga for clinical PET imaging for many years. The reconstructed image data were transferred to an imaging core laboratory for analysis, along with information about ancillary equipment such as the radionuclide dose calibrator. Fourteen PET systems were assessed from 10 nuclear medicine facilities in Australia, with the aim for each PET system being to produce images within 5% of the true SUV.Results:
At initial testing, 10 of the 14 PET systems underestimated the SUV by 15% on average (range, 13%-23%). Multiple PET systems at one site, from two different manufacturers, were all similarly affected, suggesting a common cause. We eventually identified an incorrect factory-shipped dose calibrator setting from a single manufacturer as being the cause. The calibrator setting for 68Ga was subsequently adjusted by the users so that the reconstructed images produced accurate values.Conclusion:
PET imaging involves a chain of measurements and calibrations to produce accurate quantitative performance. Testing of the entire chain is simple, however, and should form part of any quality assurance program or prequalifying site assessment before commencing a quantitative imaging trial or clinical imaging.Palavras-chave
Texto completo:
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Temas:
ECOS
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Aspectos_gerais
Bases de dados:
MEDLINE
Assunto principal:
Doses de Radiação
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Achados Incidentais
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Tomografia por Emissão de Pósitrons
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Radioisótopos de Gálio
Tipo de estudo:
Clinical_trials
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Diagnostic_studies
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Guideline
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Prognostic_studies
Limite:
Humans
Idioma:
En
Revista:
J Nucl Med
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
Austrália