Imaging of FTLD-tau Using [18F]AV-1451

Frontotemporal lobar degeneration is a family of heterogenous syndromes with underlying protein pathology including tau, TDP-43, and FUS. There is considerable overlap in the different clinical phenotypes of frontotemporal lobar degeneration and pathological diagnosis of the causative protein is not possible in vivo. The positron emission tomography radioligand [18F]AV-1451 demonstrates specificity to tau protein in Alzheimerâ s disease. The aim of this study was to investigate whether frontotemporal lobar degeneration due to tau protein accumulation could be distinguished from frontotemporal lobar degeneration caused by TDP-43 and controls using [18F]AV-1451. There were no brain regions where [18F]AV-1451 retention was elevated compared to the other groups. In addition, [18F]AV-1451 retention did not correlate to tau localization in autopsy-confirmed progressive supranuclear palsy. [18F]AV-1451 may not have suitable characteristics necessary for detecting tau deposition in frontotemporal lobar degeneration. Ongoing studies will help understand the relationship between [18F]AV-1451 retention and tau deposition in frontotemporal lobar degeneration.M.Sc