PT  - JOURNAL ARTICLE
AU  - Okuda, Kyohei
AU  - Hasegawa, Daisuke
AU  - Kamiya, Takashi
AU  - Ichikawa, Hajime
AU  - Umeda, Takuro
AU  - Ohkubo, Takushi
AU  - Miwa, Kenta
TI  - Multicenter Study of Quantitative SPECT: Reproducibility of <sup>99m</sup>Tc Quantitation Using a Conjugated-Gradient Minimization Reconstruction Algorithm
AID  - 10.2967/jnmt.120.256131
DP  - 2021 Jun 01
TA  - Journal of Nuclear Medicine Technology
PG  - 138--142
VI  - 49
IP  - 2
4099  - http://tech.snmjournals.org/content/49/2/138.short
4100  - http://tech.snmjournals.org/content/49/2/138.full
SO  - J. Nucl. Med. Technol.2021 Jun 01; 49
AB  - This multicenter study aimed to determine the reproducibility of quantitative SPECT images reconstructed using a commercially available method of ordered-subset conjugate-gradient minimization. Methods: A common cylindric phantom containing a 100 kBq/mL concentration of 99mTc-pertechnetate solution in a volume of 7 L was scanned under standard imaging conditions at 6 institutions using the local clinical protocol of each. Interinstitutional variation among the quantitative SPECT images was evaluated using the coefficient of variation. Dose calibrator accuracy was also investigated by measuring the same lot of commercially available 99mTc vials at each institution. Results: The respective radioactivity concentrations under standard and clinical conditions ranged from 95.71 ± 0.60 (mean ± SD) to 108.35 ± 0.36 kBq/mL and from 96.78 ± 0.64 to 108.49 ± 0.11 kBq/mL, respectively. Interinstitutional variation in radioactivity concentration was 4.20%. The bias in the radioactivity concentrations in SPECT images was associated with the accuracy of the dose calibrator at each institution. Conclusion: The reproducibility of the commercially available quantitative SPECT reconstruction method is high and comparable to that of PET, for comparatively large (∼7 L), homogeneous objects.