Figure 2.
Amyloid-β (Aβ) immunohistochemistry demonstrating cerebral amyloid angiopathy (CAA) severity scale in parenchymal blood vessels. (A) CAA in a narrow artery with a focal aggregation of Ab immunopositivity. A section in which this pattern predominates was designated “Stage 1” CAA. (B) A case in which there are many parenchymal Ab plaques but there is only scattered CAA of intermediate severity (arrow), which would be designated “Stage 2” CAA. (C) A section with minimal parenchymal Ab plaques but relatively strong uniform Ab immunostaining of vessels (arrows); this would still be “Stage 3” CAA. (D) Many cases with “Stage 3” CAA showed strong Ab immunopositivity outlining small blood vessels, including capillaries (arrows). Scale bars: A, C, = 200 mm; B, 50 mm; D, 40 mm.