15. Brain, Acute Infarct - Low Power
Acute infarct (anoxic necrosis) of Sommer sector of the pyramidal
layer of the hippocampus. NOTE: This view is mainly for orientation.
Acute anoxic necrosis is apparent as slight pallor and focal
hypereosinophila at this power. The hypereosinophila is due to the
acutely necrotic neurons, and the pallor is probably related to
associated cerebral edema. In the hippocampus, in adults, Sommer
sector of the pyramidal layer of the hippocampus is very sensitive to
global hypoxic/ischemic injury, and might suffer infarction in the
abscence of vascular occlusion for this reason. Compare the expected
patterns in focal infarcts, watershed infarcts, and global
hypoxic-ischemic encephalopathy.
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