title: Assessment of accuracy of PET utilizing a 3-D phantom to simulate the activity distribution of [18F]fluorodeoxyglucose uptake in the human brain.
abstract: A three-dimensional brain phantom has been developed to simulate the activity distributions found in human brain studies currently employed in positron emission tomography (PET). The phantom has a single contiguous chamber and utilizes thin layers of lucite to provide apparent relative concentrations of 5, 1, and 0 for gray matter, white matter, and CSF structures, respectively. The phantom and an ideal image set were created from the same set of data. Thus, the user has a basis for comparing measured images with an ideal set that allows a quantitative evaluation of errors in PET studies with an activity distribution similar to that found in patients. The phantom was employed in a study of the effect of deadtime and scatter on accuracy in quantitation on a current PET system. Deadtime correction factors were found to be significant (1.1-2.5) at count rates found in clinical studies. Deadtime correction techniques were found to be accurate to within 5%. Scatter in emission and attenuation correction data consistently caused 5-15% errors in quantitation, whereas correction for scatter in both types of data reduced errors in accuracy to less than 5%.
authors.affiliation: Division of Nuclear Medicine and Biophysics, UCLA School of Medicine 90024.
authors.forename: E J
authors.initials: EJ
authors.lastname: Hoffman
authors.forename: P D
authors.initials: PD
authors.lastname: Cutler
authors.forename: T M
authors.initials: TM
authors.lastname: Guerrero
authors.forename: W M
authors.initials: WM
authors.lastname: Digby
authors.forename: J C
authors.initials: JC
authors.lastname: Mazziotta
mesh_terms: D001921:Brain / Q000000981:diagnostic imaging* / Q000378:metabolism; D003847:Deoxyglucose / Q000031:analogs & derivatives* / Q000378:metabolism / Q000493:pharmacokinetics; D005462:Fluorine Radioisotopes; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008954:Models, Biological; D008961:Models, Structural; D014018:Tissue Distribution; D014055:Tomography, Emission-Computed / Q000592:standards*
chemical_list: D005462:Fluorine Radioisotopes; D019788:Fluorodeoxyglucose F18; D003847:Deoxyglucose