MAPT and Alzheimer disease: PET imaging of [11C]PBB3 bio tracer deposition is beneficial for differential diagnosis between AD and frontotemporal lobar degeneration (FTLD). Accumulation of bio tracers [11C]PBB3 and [11C]PiB was significantly higher in patients with AD than in FTLD and strongly positively correlated to tau protein deposition. Additionally, [18F]FDG SUVR was reduced in the temporal and parietal lobes of participants with AD. Detection in CSF of tau protein and Aβ amyloid did not correlate with SUVR of bio tracers.