Positron Emission Tomography (PET) in Dementias



As human life expectancy increases, dementias have become a growing public health issue. Since dementias have many types/subtypes associated with different genetics, molecular mechanisms, neurohistopathology, and clinical courses, accurate diagnosis of dementias is imperative for the implementation of effective pharmacotherapy and for optimizing patient care. Clinical nuclear medicine neuroimaging is increasingly utilized for the evaluation of dementias. Presently, 18F-fluorodeoxyglucose positron emission tomography (FDG PET) is the most commonly used functional neuroimaging modality to aid the clinical diagnosis of dementias (Ishii, Am J Neuroradiol 35:2030–2038, 2014). Presented in this chapter are original clinical cases with probably normal PET findings or with altered brain metabolism in patterns suggestive of the following neurological conditions: normal aging, mild cognitive impairment (MCI), Alzheimer’s disease (AD), frontotemporal dementias (FTD), dementia with Lewy bodies (DLB), vascular dementia (VD), mixed dementias, corticobasal degeneration (CBD), dementia secondary to major depression disorder (MDD), brain tumors or vascular malformation, and dementia of unknown type. Since 2012, beta-amyloid PET has become a new clinical neuroimaging modality (Filippi et al., Am J Nucl Med Mol Imaging 8:268–281, 2018). A negative beta-amyloid PET effectively rules out AD – the most common type of amyloid dementia. A positive beta-amyloid PET depicts significant beta-amyloid deposition in the brain, but is not by itself indicative of AD, nor exclusive of coexisting neurologic disorders other than AD. Moreover, a positive beta-amyloid PET could occur in some elder individuals without cognitive impairment.


PET FDG Beta-amyloid Hypometabolism Dementias Alzheimer’s disease 


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© Springer Nature Switzerland AG 2020

Authors and Affiliations

  1. 1.Department of Diagnostic Radiology & Molecular ImagingOakland University William Beaumont School of MedicineRoyal OakUSA

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