The standardized uptake value (SUV) is a nuclear medicine term, used in positron emission tomography (PET) as well as in modern calibrated single photon emission tomography (SPECT) imaging for a semiquantitative analysis.[1] Its use is particularly common in the analysis of [18F]fluorodeoxyglucose ([18F]FDG) images of cancer patients. It can also be used with other PET agents especially when no arterial input function is available for more detailed pharmacokinetic modeling. Otherwise measures like the fractional uptake rate (FUR) or parameters from more advanced pharmacokinetic modeling may be preferable.
Abnormal SUV values indicate variations in metabolic activity and thus can provide identifying areas of interest, like tumors or regions of inflammation. [2]
The SUV is the ratio of the image-derived radioactivity concentration cimg and the whole body concentration of the injected radioactivity cinj,