Capillary amyloid angiopathy. Pan-amyloid-beta (pan-Aβ) immunohistochemistry. (a) A diffuse plaque of Aβ in cerebral cortex with a capillary, devoid of Aβ, running through it. Cortical capillaries are surrounded by (b) a thin layer of Aβ corresponding to the perivascular basement membrane (c) with attached globular deposits of Aβ (Drusen) continuous with Aβ in the capillary wall. (d) Globular Aβ Drusen partly surround the capillary wall. Confocal images were stained with thioflavin S. (e) Histological section of a cortical capillary with a spiky Druse of amyloid continuous with amyloid in the capillary wall. (f) Smear preparations of multiple globular Drusen and (g) filiform deposits of amyloid attached to cortical capillaries whose walls also stain for amyloid. (h) Higher magnification shows continuity of the filaments with amyloid in the capillary wall. Scale bars = 20 μm (a-d, f-h) and 10 μm (e). Reprinted with permission from John Wiley & Sons, Inc. .