Our results are in line with data from 2 recent autopsy studies on 2 patients with CBD who were scanned using 18F-AV-1451 in life and where tau pathology was assessed neuropathologically postmortem.8,9 These studies suggest that there is an in vivo affinity of AV-1451 also for the 4R tau pathology in CBD, but this affinity is lower than for the 3R and 4R paired helical filaments of AD. Here, MAPT is linked to Alzheimer disease.