The application of positron-emitting molecular imaging tracers in Alzheimer's disease.

The symptomatology and known pathology of Alzheimer's disease are restricted to the central nervous system. This review details studies of PET tracers aimed at interrogating cholinergic, serotonergic, opiate, benzodiazepine, and inflammatory pathways as well as PET tracers that illuminate amyloid plaques and neurofibrillary tangles in AD. Progress has been remarkable. Together with studies of brain structure with MRI and of functional regional brain activity, e.g., through measures of blood flow and glucose metabolic rate, molecular imaging promises to dramatically alter our understanding of the structural and physiological abnormalities underlying AD symptomatology. A more immediate impact on the diagnosis and treatment evaluation of AD patients in clinical trials is predicted while the possibility of personalized treatment or prevention of AD may not be that far away.