ACTA1 and Alzheimer disease: Therefore, we systematically quantified Braak stage- and CAA-dependent and -independent changes in collagen, elastin, and α-SMA and luminal diameters of the leptomeningeal arterioles, small arteries, and medium-sized arteries surrounding the gyrus frontalis medialis (GFM) and hippocampus (HIPP), including the sulci, of non-demented control (NDCTRL) and AD subjects.