Figure 11.

β-amyloid staining. Photomicrograph of the midfrontal cortex with amyloid-β-5 staining in a patient with dementia shows numerous aggregates of extracellular amyloid plaque (circles). Amyloid deposition is also depicted along adjacent vascular walls (arrow). These aggregates are the site of binding of amyloid PET radiotracers. Although the presence of amyloid aggregates is sensitive for the detection of Alzheimer disease, it is not highly specific and can be visualized in Alzheimer disease and certain cases of dementia with Lewy bodies (DLB). The significance of these plaques is still not well understood, and they may be either primary or secondary findings to the underlying disease process.