16. Cerebral infarction. A, at low magnification, it is possible to see the demarcated areas of an acute infarction. In the underlying white matter, the areas of infarction are well shown by the myelin stain. B, acute ischemic injury causes diffuse eosinophilia of neurons, which are beginning to shrink. C, infiltration of a cerebral infarct by neutrophils begins at the edges of the lesion where vascular supply has remained intact. D, after about 10 days, an area of infarction is characterized by the presence of macrophages and surrounding reactive gliosis. E, Remote small intracortical infarcts are seen as areas of tissue loss with a small amount of residual gliosis.
87. Epidural hematoma (left) in which rupture of meningeal artery, usually associated with a skull fracture, leads to accumulation of arterial blood between the dura and the skull. In a subdural hematoma (right), damage to bridging veins between the brain and the superior sagittal sinus leads to the accumulation of blood between the dura and the arachnoid.
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89. Epidural hematoma covering a portion of the dura. Multiple small contusions are seen in the temporal lobe.
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93. A, Large organizing subdural hematoma attached to the dura. B, Coronal section of the brain showing compression of the hemisphere underlying the hematoma.