The diagnostic difference between 18F- FDG PET and 99mTc-HMPAO SPECT perfusion imaging in assessment of Alzheimer's disease

Document Type : Original Article


1 Radiology Department, Faculty of Medicine, Zagazig University, Zagazig, Egypt

2 Radiology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt


Introduction:Brain imaging with F-18 fluorodeoxyglucose (18F-FDG) positron ‎emission tomography or Tc-99m hexamethylpropyleneamine oxime (‎99mTc-HMPAO) SPECT is widely used for the evaluation of Alzheimer's ‎dementia (AD); we aim to assess superiority of one method over the ‎other.
Methods: Twenty four patients with clinical diagnosis of Alzheimer disease ‎underwent 18F-FDG PET and ‎99mTc-HMPAO SPECT in order to ‎assess the zones of hypo metabolism & hypoperfusion specific for ‎Alzheimer's disease.
Results: 18F-FDG PET showed specific zones of ‎hypometabolism in 19 patients (79.1%) while SPECT was positive in 15 ‎cases (62.5%) with statistically significant difference (P= 0.027).

Conclusion: 18F-FDG PET was significantly superior to HMPAO ‎SPECT and 18F-FDG PET could replace the classic role of perfusion ‎SPECT in diagnosis of Alzheimer's disease.


Main Subjects

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