MAPT and Alzheimer disease: [18F]-THK523 selectively binds to paired helical filament tau in AD brains but does not bind to tau lesions in non-AD tauopathies, such as corticobasal degeneration (CBD), progressive supranuclear palsy (PSP) and Pick’s disease (PiD), or to α-synuclein containing Lewy bodies in PD brains [19].