Clinical and Translational Imaging

, Volume 7, Issue 6, pp 437–445 | Cite as

18F-FDG in the differential diagnosis of neurodegenerative dementias

  • Angelo Del SoleEmail author
  • Veronica Redaelli
  • Paola Caroppo
  • Alberto Priori
Pictorial Essay
Part of the following topical collections:
  1. Neuroimaging


The diagnostic workflow of patients with cognitive decline needs an extensive clinical evaluation. The use of FDG-PET can be helpful because the finding of a rather specific pattern of hypometabolism could point to specific neurodegenerative disorders. In patients with memory impairment and visuo-spatial deficits, FDG-PET may reveal a pattern of temporo-parietal hypometabolism that is associated with Alzheimer’s disease or a more extended area of hypometabolism that spreads to the occipital cortex, as in posterior cortical atrophy indicating signs of neurodegeneration in the associative visual cortex. In the spectrum of fronto-temporal lobe degeneration, FDG-PET is used to support the diagnosis by excluding AD and to identify areas of hypometabolism that are associated with the behavioural variant of FTD or with progressive primary aphasia. When cognitive impairment develops along with parkinsonism, FDG-PET can be used to differentiate among the different forms of disorders, such as dementia with Lewy bodies, progressive supranuclear palsy and cortico-basal degeneration, occurring with different specific pattern of altered metabolism. In this pictorial essay, we present a series of clinical cases in which the use of FDG-PET contributed to the final diagnosis.


Dementia AD DLB PSP CBD 


Author contributions

All the authors contributed equally to the literature review, planning, writing of the text, selection and preparation of the cases presented.

Compliance with ethical standards

Conflict of interest

Angelo Del Sole, Veronica Redaelli, Paola Caroppo, Alberto Priori declare no conflict of interest.

Informed consent

All patients gave written consent for the publication of their PET images and clinical data in anonymous form.


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Copyright information

© Italian Association of Nuclear Medicine and Molecular Imaging 2019

Authors and Affiliations

  1. 1.Nuclear Medicine UnitASST Santi Paolo e CarloMilanItaly
  2. 2.Aldo Ravelli Foundation for Neurotechnology and Experimental Brain Therapeutics and Department of Health SciencesUniversity of MilanMilanItaly
  3. 3.Unit of Neurology 5, NeuropathologyFondazione IRCCS Istituto Neurologico Carlo BestaMilanItaly

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