Tissue necrosis in any area of the brain, including the cerebral hemispheres, the cerebellum, and the brain stem. Brain infarction is the result of a cascade of events initiated by inadequate blood flow through the brain that is followed by hypoxia and hypoglycemia in brain tissue. Damage may be temporary, permanent, selective or pan-necrosis. The disease is MONDO_0005394 (brain infarction).