SPECT in dementia: clinical and pathological correlation

J Am Geriatr Soc. 1995 Nov;43(11):1243-7. doi: 10.1111/j.1532-5415.1995.tb07400.x.


Background: The clinical diagnosis of dementia continues to be flawed. Although the diagnosis of Alzheimer's disease (AD) is better than 90% at research centers in highly selected patients, the diagnosis of patients with non-AD dementias and atypical AD patients is poor. Single photon emission computed tomography (SPECT) is a functional imaging technique touted as a diagnostic technique for the degenerative disorders. However there have been few clinicopathological studies using SPECT.

Methods: Twenty-seven consecutive dementia patients were evaluated clinically at a University-based specialty dementia clinic, and a diagnosis of a specific dementia was made. SPECT imaging was used in helping to select a clinical diagnosis. The correlations between clinical, SPECT and autopsy diagnoses were analyzed.

Results: Single photon emission computed tomography predicted pathologic diagnosis in 25 of 27 patients with dementia (92.6%), compared with clinical diagnosis, which was confirmed in 20/27 (74.1%). Distinct patterns were associated with dementia caused by AD, Fronto-Temporal Dementia (FTD), and Jakob-Creutzfeldt Disease (JCD). Vascular insults not seen with computerized tomography (CT) or magnetic resonance imaging (MRI) were found with SPECT. Three different pathologies were found in patients with Parkinsonian-Dementias (PD): Lewy-Body Variant of AD, Diffuse Lewy-bodies without plaques, and substantia nigra neuronal loss without plaques or Lewy-bodies. All showed a temporal-parietal pattern with SPECT that was similar to AD.

Conclusion: SPECT provides useful positive information in dementia, particularly the differentiation of AD, FTD, and JCD. However, it does not distinguish PD from AD.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Alzheimer Disease / diagnostic imaging*
  • Alzheimer Disease / pathology
  • Creutzfeldt-Jakob Syndrome / diagnostic imaging
  • Creutzfeldt-Jakob Syndrome / pathology
  • Dementia / diagnostic imaging*
  • Dementia / pathology
  • Diagnosis, Differential
  • Female
  • Humans
  • Male
  • Middle Aged
  • Predictive Value of Tests
  • Tomography, Emission-Computed, Single-Photon*