title: Quantitative approaches to amyloid imaging.
abstract: Alzheimer's disease (AD), an irreversible, progressive neurodegenerative disorder clinically characterized by memory loss and cognitive decline, is the leading cause of dementia in the elderly, leading invariably to death within 7-10 years after diagnosis. In vivo amyloid imaging with positron emission tomography (PET) is allowing new insights into β-amyloid (Aβ) deposition in the brain, facilitating research into the causes, diagnosis, and future treatment of dementias, where Aβ may play a role. Non-invasive quantification of Aβ burden in the brain with PET has proven useful in the early and differential diagnosis of dementias, showing significantly higher retention in grey matter of AD patients when compared with healthy controls (HC) or patients with frontotemporal lobe degeneration (FTLD). With the advent of new therapeutic strategies aimed at reducing Aβ burden in the brain to potentially prevent or delay functional and irreversible cognitive loss, there is increased interest in developing agents that allow assessment of Aβ burden in vivo. A key aspect for Aβ burden quantification is the application of compartmental or graphical analyses to the kinetic data in order to obtain quantitative and reproducible statements that allow comparison with other nosological groups, correlation with cognitive or biological parameters, and selection, monitoring, and follow-up of individuals in disease modifying therapeutic trials. It is also a necessary step in the validation of simplified approaches that could be applied in routine clinical settings. With the availability of novel amyloid imaging agents radiolabeled with either (11)C (half-life 20 min) or (18)F (half-life 110 min), a description of different image acquisition approaches is provided.
authors.affiliation: Department of Nuclear Medicine, Centre for PET, Austin Health, Heidelberg, VIC 3084, Australia. villemagne@petnm.unimelb.edu.au
authors.forename: Victor L
authors.initials: VL
authors.lastname: Villemagne
authors.forename: Graeme
authors.initials: G
authors.lastname: O'Keefe
authors.forename: Rachel S
authors.initials: RS
authors.lastname: Mulligan
authors.forename: Christopher C
authors.initials: CC
authors.lastname: Rowe
mesh_terms: D000544:Alzheimer Disease / Q000473:pathology*; D000682:Amyloid / Q000648:ultrastructure*; D002250:Carbon Radioisotopes; D005462:Fluorine Radioisotopes; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D007553:Isotope Labeling / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D049268:Positron-Emission Tomography / Q000379:methods*; D012984:Software
chemical_list: D000682:Amyloid; D002250:Carbon Radioisotopes; D005462:Fluorine Radioisotopes