Differential diagnosis of neurodegenerative dementias using metabolic phenotypes on F-18 FDG PET/CT

Neuroradiol J. 2014 Feb;27(1):13-21. doi: 10.15274/NRJ-2014-10002. Epub 2014 Feb 24.


Positron emission tomography (PET) imaging with F-18 fluorodeoxyglucose (FDG) can be used as a downstream marker of neuronal injury, a hallmark of neurodegenerative dementias. Characteristic patterns of regional glucose metabolism have been used to classify the dementia subtypes, namely Alzheimer's dementia (AD), frontotemporal dementia (FTD), diffuse Lewy body (DLBD) and vascular dementia (VD). We undertook this study to assess the utility of FDG-PET in the differential diagnosis of dementia subtypes. One hundred and twenty-five patients diagnosed with dementia were referred from cognitive disorders and memory clinics of speciality neurology centres for the FDG-PET study. Imaging-based diagnosis of dementia type was established in 101 patients by visual assessment of individual scans by a PET physician blinded to the clinical diagnosis. The results were compared with an 18-month follow-up clinical assessment made by the specialist neurologist. Concordance of visual evaluation of FDG-PET scans with clinical diagnosis of the dementia type was achieved in 90% of patients scanned. This concordance was 93.4% for AD, 88.8% for FTD, 66.6% for DLBD and 92.3% for the other dementia syndromes. FDG-PET performed after the initial work-up of dementias is useful for supporting the clinical diagnosis of dementia subtype.

Keywords: AD; DLBD; FDG-PET; FTD; vascular dementia.

MeSH terms

  • Aged
  • Alzheimer Disease / diagnostic imaging
  • Alzheimer Disease / metabolism
  • Creutzfeldt-Jakob Syndrome / diagnostic imaging
  • Creutzfeldt-Jakob Syndrome / metabolism
  • Dementia / diagnostic imaging*
  • Dementia / metabolism*
  • Dementia / psychology
  • Dementia, Vascular / diagnostic imaging
  • Dementia, Vascular / metabolism
  • Diagnosis, Differential
  • Female
  • Fluorodeoxyglucose F18 / metabolism*
  • Frontotemporal Dementia / diagnostic imaging
  • Frontotemporal Dementia / metabolism
  • Humans
  • Lewy Body Disease / diagnostic imaging
  • Lewy Body Disease / metabolism
  • Male
  • Middle Aged
  • Neurodegenerative Diseases / diagnostic imaging*
  • Neurodegenerative Diseases / metabolism
  • Neuropsychological Tests
  • Phenotype
  • Positron-Emission Tomography* / methods
  • Radiopharmaceuticals / metabolism*
  • Reproducibility of Results
  • Tomography, X-Ray Computed


  • Radiopharmaceuticals
  • Fluorodeoxyglucose F18