Participants underwent structural MRI and a dual-phase Florbetapir-PET scanning at the Cyceron Center (Caen, France) on a Philips Achieva 3T scanner (Eindhoven, The Netherlands) and a Discovery RX VCT 64 PET-CT scanner (General Electric Healthcare, Milwaukee, WI), respectively. Acquisition details have been previously reported6 (link),35 (link) and are available in eMethods, links.lww.com/WNL/C821.