MAPT and vascular disorder: This observation could be suggestive of a possible relationship between leptomeningeal Aβ vasculopathy and cerebral tau pathologies, as cSS has been associated with a higher severity of CAA in the leptomeningeal vessels, but not in the cortical vessels.40 Additionally, pathological analyses have found tau-immunopositive neurites around amyloid-laden vessels,7-9 implying a potential interaction between CAA and perivascular accumulation of hyperphosphorylated tau.