The Pattern of Brain Amyloid Load in Posterior Cortical Atrophy Using (18)F-AV45: Is Amyloid the Principal Actor in the Disease?

BACKGROUND:Posterior cortical atrophy (PCA) is characterized by progressive higher-order visuoperceptual dysfunction and praxis declines. This syndrome is related to a number of underlying diseases, including, in most cases, Alzheimer's disease (AD). The aim of this study was to compare the amyloid load with (18)F-AV45 positron emission tomography (PET) between PCA and AD subjects. METHODS:We performed (18)F-AV45 PET, cerebrospinal fluid (CSF) biomarker analysis and a neuropsychological assessment in 11 PCA patients and 12 AD patients. RESULTS:The global and regional (18)F-AV45 uptake was similar in the PCA and AD groups. No significant correlation was observed between global (18)F-AV45 uptake and CSF biomarkers or between regional (18)F-AV45 uptake and cognitive and affective symptoms. CONCLUSION:This (18)F-AV45 PET amyloid imaging study showed no specific regional pattern of cortical (18)F-AV45 binding in PCA patients. These results confirm that a distinct clinical phenotype in amnestic AD and PCA is not related to amyloid distribution.