Computed Tomography and Positron Emission Transaxial Tomography Evaluations of Normal Aging and Alzheimer's Disease

Abstract

Summary: Young normal subjects, old normal subjects, and patients with senile dementia of the Alzheimer's type (SDAT) were studied with both computed tomography (CT) and positron emission transaxial tomography (PETT). Increases in ventricular size with both aging and disease were measured. Regional glucose metabolic rate was not affected by age, but was markedly reduced in SDAT pa tients. These data indicate that in normal aging, structural brain changes may be more salient than biochemical Abbreviations used: CM, Canthomeatal; CT, computed to mography; FDG, 18F-2-deoxy-2-fluoro-D-glucose; GDS, Global Deterioration Scale; PETT, positron emission transaxial tomog raphy; SDAT, senile dementia of the Alzheimer's type. It is possible that a number of methodological variables, such as subject selection criteria and methods of scan analysis, may account for these

Reevaluating the Role of Vascular Changes in the Differential Diagnosis of Alzheimer’s Disease and Vascular Dementia

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Cerebral Blood Flow and Metabolism in Normal Human Aging, Pathological Aging, and Senile Dementia

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Age-Related Regional Network of Magnetic Resonance Imaging Gray Matter in the Rhesus Macaque

“…Such human studies, however, cannot exclude the possibility of underlying disease pathology for which clinical symptoms have not yet emerged. Brain regions, including parietotemporal and frontal association areas, that show prominent cerebral metabolic reductions in Alzheimer's disease (AD) with functional neuroimaging (Frackowiak et al, 1981;de Leon et al, 1983;Duara et al, 1986;Silverman et al, 2001;Alexander et al, 2002) also show decrements in individuals without clinical symptoms but with increased genetic risk for AD (Reiman et al, 1996(Reiman et al, , 2005.…”