Post-Mortem evaluation of amyloid-dopamine terminal positron emission tomography dementia classifications.
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ABSTRACT:
SUBMITTER: Albin RL
PROVIDER: S-EPMC4836870 | biostudies-literature | 2015 Nov
REPOSITORIES: biostudies-literature
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Post-Mortem evaluation of amyloid-dopamine terminal positron emission tomography dementia classifications.
Albin Roger L RL Fisher-Hubbard Amanda A Shanmugasundaram Krithika K Koeppe Robert A RA Burke James F JF Camelo-Piragua Sandra S Lieberman Andrew P AP Giordani Bruno B Frey Kirk A KA
Annals of neurology 20150825 5
Clinical classification of early dementia and mild cognitive impairment (MCI) is imprecise. We reported previously that molecular imaging classification of early dementia and MCI with dual amyloid and dopamine terminal positron emission tomography differs significantly from expert clinical classification. We now report pathological diagnoses in a substantial subset of our previously imaged subjects. Among 36 subjects coming to autopsy, imaging classifications and pathological diagnosis were conc ...[more]
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Project description:BackgroundPittsburgh compound B ([11C]-PIB) identifies amyloid-β (Aβ) deposition in vivo. Asymptomatic Aβ deposition has been reported consistently in some healthy older subjects. Of patients with frontotemporal dementia, those who have later onset have a higher potential for Aβ deposition.ObjectiveComparison of Aβ deposition in Alzheimer's disease (AD), healthy older controls, and patients with early- and late-onset semantic dementia (SD), a subtype of frontotemporal dementia.MethodsSubjects were recruited from tertiary academic care centers specializing in assessment and management of patients with neurodegenerative disease. We used the radiotracer [11C]-PIB in a high-resolution positron emission tomography scanner to evaluate 11 participants with SD (six with onset before age 65 and five with later onset), 9 with probable AD, and 10 controls over age 60. The main outcome measures were frontal, temporal, parietal, and total [11C]-PIB standardized uptake value ratios to establish PIB-positive (PIB+) cutoff.ResultsThe five patients with late-onset SD were PIB-negative. Two of six with early-onset SD, seven of nine with AD, and 1 of 10 controls were PIB+. The SD participants who were PIB+ did not have memory or visuospatial deficits that are typical in AD.ConclusionsAβ deposition does not seem to be associated with late-onset SD. Future larger studies might confirm whether a significant minority of early-onset SD patients exhibit Aβ deposition. Copyright © 2016 John Wiley & Sons, Ltd.
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