Fig. 2.
18F-florbetapir amyloid PET and thioflavin-S amyloid plaque density show close correspondence. A The florbetapir PET standard uptake value ratio (SUVR) image, acquired 19 months before death, referenced by the whole cerebellum and without partial volume correction (PVC), overlaid on the participants MRI in native space. A coronal and four descending axial slices are displayed. The white arrow points towards the focal binding in the left superior temporal region. B The same PET data as in A with volume-to-MRI-surface projection and PVC applied. The focality and asymmetry of uptake were pronounced, specifically in the left middle frontal, superior temporal, and precuneus regions. C The eight color bars on the native MRI surface reconstruction indicate where postmortem dissections and stereological counting was performed. D There was a strong correlation between thioflavin-S amyloid plaque density and florbetapir PET SUVR across the eight regions (r = 0.92, p = 0.0013). (E) Photomicrographs from the fluorescent thioflavin-S staining, from the middle temporal region and entorhinal region, at 40× and 20× magnification