Quantitative Analysis of Amyloid Deposition in Alzheimer Disease Using PET and the Radiotracer 11C-AZD2184

Characteristic neuropathologic changes in Alzheimer disease (AD) are amyloid-β deposits and neurofibrillary tangles. Recently, a new radioligand for amyloid senile plaques, 11C-labeled 5-(6-{[tert-butyl(dimethyl)silyl]oxy}-1,3-benzothiazol-2-yl)pyridin-2-amine (11C-AZD2184), was developed, and it was reported to show rapid brain uptake followed by rapid washout. In this study, 11C-AZD2184 bind-ing in control subjects and AD patients was examined in more detail by compartment model analysis using a metabolite-corrected ar-terial input function. The accuracy of simplified quantitative meth-ods using a reference brain region was also evaluated. Methods: After intravenous bolus injection of 11C-AZD2184, a dynamic PET scan was obtained for 90 min in 6 control subjects and 8 AD patients. To obtain the arterial input function, arterial blood sam-pling and high-performance liquid chromatography analysis were performed. Results: Time–activity curves in all brain regions coul