CenTauR: Toward a universal scale and masks for standardizing tau imaging studies.

Introduction: Recently, an increasing number of tau tracers have become available. There is a need to standardize quantitative tau measures across tracers, supporting a universal scale. We developed several cortical tau masks and applied them to generate a tau imaging universal scale.

Method: One thousand forty-five participants underwent tau scans with either F-flortaucipir, F-MK6240, F-PI2620, F-PM-PBB3, F-GTP1, or F-RO948. The universal mask was generated from cognitively unimpaired amyloid beta (Aβ)- subjects and Alzheimer's disease (AD) patients with Aβ+. Four additional regional cortical masks were defined within the constraints of the universal mask. A universal scale, the CenTauR, was constructed.

Results: None of the regions known to display off-target signal were included in the masks. The CenTauR allows robust discrimination between low and high levels of tau deposits.

Discussion: We constructed several tau-specific cortical masks for the AD continuum and a universal standard scale designed to capture the location and degree of abnormality that can be applied across tracers and across centers. The masks are freely available at https://www.gaain.org/centaur-project.