PT  - JOURNAL ARTICLE
AU  - Gnesin, Silvano
AU  - Mikell, Justin K.
AU  - Conti, Maurizio
AU  - Prior, John O.
AU  - Carlier, Thomas
AU  - Lima, Thiago V.M.
AU  - Dewaraja, Yuni K.
TI  - A Multicenter Study on Observed Discrepancies Between Vendor-Stated and PET-Measured <sup>90</sup>Y Activities for Both Glass and Resin Microsphere Devices
AID  - 10.2967/jnumed.122.264458
DP  - 2023 May 01
TA  - Journal of Nuclear Medicine
PG  - 825--828
VI  - 64
IP  - 5
4099  - http://jnm.snmjournals.org/content/64/5/825.short
4100  - http://jnm.snmjournals.org/content/64/5/825.full
SO  - J Nucl Med2023 May 01; 64
AB  - Dosimetry-guided treatment planning in selective internal radiation therapy relies on accurate and reproducible measurement of administered activity. This 4-center, 5-PET-device study compared the manufacturer-declared 90Y activity in vials with quantitative 90Y PET/CT assessment of the same vials. We compared 90Y PET-measured activity (APET) for 56 90Y-labeled glass and 18 90Y-labeled resin microsphere vials with the calibrated activity specified by the manufacturer (AM). Additionally, the same analysis was performed for 4 90Y-chloride vials. The mean APET/AM ratio was 0.79 ± 0.04 (range, 0.71–0.89) for glass microspheres and 1.15 ± 0.06 (range, 1.05–1.25) for resin microspheres. The mean APET/AM ratio for 90Y-chloride vials was 1.00 ± 0.04 (range, 0.96–1.06). Thus, we found an average difference of 46% between glass and resin microsphere activity calibrations, whereas close agreement was found for chloride solutions. We expect that the reported discrepancies will promote further investigations to establish reliable and accurate patient dosimetry and dose–effect assessments.