Axial FDG-PET images show relative hypometabolism in the
temporal and posterior parietal lobes, confirmed on whole brain MIP image
projected in the sagittal plane.
Alzheimer’s disease (AD) is the most common cause of
dementia with increasing prevalence as United States and world populations age.
The disease is characterized clinically by memory impairment and progressive
dysfunction in cognition with personality changes late in the course. Pathologically, neurofibrillary tangles,
senile plaques, and amyloid angiopathy are seen with disruption of axonal
Traditional imaging modalities are insensitive for early
disease and may demonstrate nonspecific atrophy late in the disease course.
Functional imaging with FDG PET has increased both sensitivity and specificity
for AD when characteristic temporoparietal hypometabolism is observed.
Norfray JF, Provenzale JM. Alzheimer’s disease: Neuropathologic findings and recent advances in imaging. AJR Am J Roentgenol. 2004;182:3-13.
Perrone, M. FDA panel sees promise in Alzheimer’s imaging drug. The Associated Press. January 20, 2011. Available online as of February 24, 2011 at: http://www.physorg.com/news/2011-01-fda-panel-alzheimer-imaging-drug.html.