Cerebral Amyloid Angiopathy (CAA) is associated with gray matter R2 relaxation rate: An ex-vivo MRI and pathology study

Cerebral amyloid angiopathy (CAA) is characterized by accumulation of amyloid-β protein in the walls of cortical and leptomeningeal small vessels. CAA is common in older adults and is associated with intracerebral hemorrhage, microbleeds, cognitive decline and dementia. The present study in a large number of community-based older adults (N=802) combined ex-vivo MRI and detailed neuropathology and showed for the first time that CAA is associated with higher transverse relaxation rate, R2, in gray matter, independent of other neuropathologies and demographics. The regions that showed this association included cortical regions in the temporal and frontal lobes as well as subcortical structures.