Ziel/Aim:
Intraneuronal aggregation of tau proteins are a hallmark of cerebral pathology in
the two of the most common forms of neurodegenerative dementia (ND): The amyloid-associated
(amy+) Alzheimer's disease (AD) and the non-amyloid associated (amy-) fronto-temporal
lobar degeneration (FTLD). In recent years, Flortaucipir and other tau PET tracers
have been developed and are being evaluated. This study investigates the ability of
Flortaucipir PET to reliably differentiate amy+ and amy- forms of ND.
Methodik/Methods:
35 patients with amy+ and 19 patients with amy- forms of ND underwent Flortaucipir
PET. PET data were subject to a purely data-driven scaled subprofile modelling/principal
component analysis (SSM/PCA; Eidelberg et al. Trends Neurosci 2009) to identify spatial
covariance patterns. SSM/PCA components were tested for their ability to differentiate
amy+ from amy- patients by measuring individual pattern expression strengths. Thresholds
were defined by a receiver operating characteristic (ROC) analysis and validated with
a leave-one-out approach.
Ergebnisse/Results:
The expression of the main (first) SSM/PCA component separated groups with a sensitivity
of 0.97 and a specificity of 0.90, (AUC = 0.97). Anatomically, group separation performance
was driven by parietooccipital grey matter binding (amy+) vs. disseminated white matter
binding (amy-).
Schlussfolgerungen/Conclusions:
Expression strength of an SSM/PCA derived binding pattern of Flortaucipir discriminates
amy+ from amy- forms of ND with high accuracy. Together with a perfusion weighted
early-phase acquisition, Flortaucipir PET alone – as a one stop shop examination –
may convey equivalent information to additional amyloid and FDG-PET to characterize
the form of ND.
