P1-285: First results toward in vivo quantification of cerebral β-amyloid plaque load in Alzheimer's disease by means of BAY 94-9172-PET

patients had significantly higher DVR reflecting greater AV-45 binding estimates in the following brain regions: frontal, temporal, fusiform gyrus, cingulate, insula, putamen, globus pallidus, as well as a summary measure of whole-cortex DVR. MMSE, WMS, and category fluency were not correlated with DVR in any brain region after controlling for diagnosis. However, regional DVR in frontal, temporal, occipital, fusiform gyrus, cingulate, parahippocampus, insula, putamen, and cortex correlated significantly with ADAS-Cog Word Recall after controlling for diagnosis (r .84-.92 for model). Similarly, regional DVR in thalamus and caudate nucleus correlated significantly with ADAS-Cog Constructional Praxis after controlling for diagnosis (r .61-.77 for model). Conclusions: DVR of [F] AV-45, a novel ligand for PET imaging of amyloid plaques, was significantly higher in AD in many cortical regions implicated in early AD. This suggests the utility of this ligand for AD diagnosis. Interestingly enough, DVR in hippocampus was not elevated reflecting the observation that neurofibrillary tangles are a more sensitive marker than plaques for early hippocampal involvement in AD. In two cognitive domains there was further evidence for correlation of cognitive performance with DVR after controlling for diagnosis, suggesting that [F] AV-45 may also be useful as a marker of AD severity.