The aim of this study was to determine the normal l-[methyl-(11)C]-methionine ((11)C-methionine) uptake and the extent of variation using standardized uptake value (SUV).
Methods: Five healthy volunteers and 58 adult patients with normal (11)C-methionine uptake were included in the interindividual analysis and 22 patients in the intraindividual analysis. SUVs in different brain regions, age-associated changes, correlation between 2 correction methods (for body weight [w-SUV] or body surface area [s-SUV]), and intraindividual reproducibility were examined.
Results: w-SUVs were statistically different between the brain regions. The frontal or parietal cortex showed lower coefficients of variation than did the cerebellum or brain stem. There was no significant age-associated change. w-SUVs showed lower coefficients of variation in interindividual analysis and lower symmetric percentage change in intraindividual reproducibility than did s-SUVs.
Conclusion: SUVs in the normal brain show inter- and intraindividual variation, and our proposed normal w-SUVs represent an important reference value.