Early detection of Alzheimer's disease with PET imaging

Abstract

Preclinical diagnosis of Alzheimer's disease (AD) is one of the major challenges for the prevention of AD. AD biomarkers are needed not only to reveal preclinical pathologic changes, but also to monitor progression and therapeutics. PET neuroimaging can reliably assess aspects of the molecular biology and neuropathology of AD. The aim of this article is to review the use of FDG-PET and amyloid PET imaging in the early detection of AD.

Fig. 1

FDG-PET scans from two representative subjects: normal subject (a) and AD subject (b). PET scans are displayed in the axial plane, from the top to the bottom of the brain, at the level of the centrum-semiovale (left), basal ganglia (center), and MTL (right). Note the hypometabolism involving parietotemporal regions, posterior cingulate/precuneus, medial temporal cortex, and to a lesser extent FC in the AD patient as compared to the normal subject.

Fig. 2

FDG-PET scan from a representative MCI subject. PET scan is displayed in the axial plane, from the top to the bottom of the brain, at the level of the centrum-semiovale (left), basal ganglia (center), and MTL (right). Note the moderate hypometabolism involving posterior cingulate/precuneus, parietal and medial temporal cortices.

Fig. 3

PIB-PET scans from two representative subjects: normal subject (a) and AD subject (b). PET scans are displayed in the axial plane, from the top to the bottom of the brain, at the level of the centrum-semiovale (left), basal ganglia (center), and MTL (right). Note that in the normal subject PIB is distributed only in the white matter, reflecting nonspecific uptake, and in the AD patient PIB uptake is present in several cortical regions, such as frontal, parietal, posterior cingulate/precuneus and lateral temporal cortices, and in basal ganglia.