Histopathology of Cerebral Ischemia and Stroke

Ischemic stroke is a serious neurological problem and one of the leading causes of death and disability worldwide. The histopathological consequences of stroke are complex and may result in a variety of deficits including severe motor and cognitive disturbances. The histopathological consequences of severe focal ischemia are well described with characteristic structural changes occurring in both gray and white brain regions depending on the severity, location, and duration of the ischemic insult. Following focal ischemic injury, neuronal, astrocytic, vascular endothelial, and inflammatory cell changes occur. In white mater tracts, axonal injury with oligodendrocyte damage and subsequent demyelination are also commonly observed. In contrast, less severe or more transient ischemic insults can lead to patterns of selective neuronal injury whereby vulnerable neuronal populations are destroyed without damage to neighboring cells or robust inflammatory responses are induced. The appreciation of these diverse histopathological characteristics associated with periods of cerebral ischemia emphasize the complexity of the pathogenesis of ischemic damage and serve as a basis for drug discovery to identify effective treatments for stroke prevention and treatment.