RT Journal Article SR Electronic T1 Comparison of the Variability of SUV Normalized by Skeletal Volume with the Variability of SUV Normalized by Body Weight in 18F-Fluoride PET/CT JF Journal of Nuclear Medicine Technology JO J. Nucl. Med. Technol. FD Society of Nuclear Medicine SP 60 OP 63 DO 10.2967/jnmt.118.215111 VO 47 IS 1 A1 José Flávio Gomes Marin A1 Paulo Schiavom Duarte A1 José Willegaignon de Amorim de Carvalho A1 Heitor Naoki Sado A1 Marcelo Tatit Sapienza A1 Carlos Alberto Buchpiguel YR 2019 UL http://tech.snmjournals.org/content/47/1/60.abstract AB Our objective was to test the hypothesis that variability in SUV normalized by skeletal volume (SV) in 18F-fluoride (18F-NaF) PET/CT studies is lower than variability in SUV normalized by body weight (BW). Methods: The mean SUV (SUVmean) was obtained for whole skeletal volume of interest (wsVOI) in 163 selected 18F-NaF PET/CT studies. These studies were performed to investigate bone metastases and were considered to have normal results. SUVmean was calculated with normalization by BW (BW SUVmean), with normalization by SV (SV SUVmean), and without normalization (WN SUVmean). The total SV for each patient was also estimated on the basis of the wsVOI defined on the CT component of the PET/CT study. SUVmean variability for each patient was estimated as the absolute value of the difference between the SUVmean for the patient and the mean of the SUVmean for the whole group of patients, divided by the mean of the SUVmean for the whole group of patients. The variabilities of SUVmean calculated by the 3 methods were compared using a paired 1-tailed Wilcoxon test. Results: The mean variability for the BW, SV, and WN SUVmean was 0.16, 0.13, and 0.16, respectively. There were statistically significant differences between SV and BW SUVmean variability (P = 0.03) and between SV and WN SUVmean variability (P < 0.01). There was no statistically significant difference between BW and WN SUVmean variability (P = 0.4). Conclusion: In patients with normal 18F-NaF PET/CT results, SV SUVmean presents lower variability than BW SUVmean.