Background: Many cases of progressive dementia are not clinically typical for Alzheimer’s disease (AD). Frontotemporal dementia (FTD) or variants are often considered, but are by no means certain clinical diagnoses. More precise diagnosis is needed.
Methods: 35 patients were studied; 12 meeting criteria for “probable AD”, and 6 judged to be FTD or one of
its variants with “high probability”. The other 17 were judged to be “atypical/possible AD/possibly FTD, and the
degree of diagnostic certainly was rated as medium to low. All were studied with FDG PET, and PET amyloid
imaging with PIB (Pittsburgh B Compound).
Results: Of those 12 subjects meeting criteria for “probable AD”, 11 remained classified as such after multi-modal
imaging, but one was reclassified as FTD. Of the 6 patients judged to be FTD with “high certainty”, four remained
as such, while two were reclassified as AD. Of the 17 rated clinically with medium to low diagnostic certainty, all
were reclassified, 15 as AD, and 2 as FTD.
Conclusions: Multi-modal imaging was successful in classifying all medium and low certainty cases in a convergent
manner.
