The Association of Age-Related and Off-Target Retention with Longitudinal Quantification of [ <sup>18</sup> F]MK6240 Tau PET in Target Regions
Cécile Tissot, Stijn Servaes, Firoza Z Lussier, João Pedro Ferrari‐Souza, Joseph Therriault, Pâmela C.L. Ferreira, Gleb Bezgin, Bruna Bellaver, Douglas Teixeira Leffa, Sulantha Mathotaarachchi, Mira Chamoun, Jenna Stevenson, Nesrine Rahmouni, Min Su Kang, Vanessa Pallen, Nina Margherita-Poltronetti, Yi-Ting Wang, Jaime Fernandez‐Arias, Andréa Lessa Benedet, Eduardo R. Zimmer, Jean‐Paul Soucy, Dana Tudorascu, Annie Cohen, Madeleine Sharp, Serge Gauthier, Gassan Massarweh, Brian J. Lopresti, William E. Klunk, Suzanne L. Baker, Victor L. Villemagne, Pedro Rosa‐Neto, Tharick A. Pascoal
Abstract
Inferior CG was similar across diagnostic groups cross-sectionally and stable over time, thus deemed a suitable reference region for quantification. Despite not being visually perceptible, [ 18 F]MK6240 has age-related retention in subcortical regions, in much lower magnitude but topographically co-localized with significant off-target signal of the first-generation tau tracers. The lack of correlation between changes in age-related/meningeal and target retention suggests little influence of possible off-target signals on longitudinal tracer quantification.