Brain ischemia can be further subdivided, by cause, into thrombotic, embolic, and hypoperfusion. Thrombotic and embolic are generally focal or multifocal in nature while hypoperfusion affects the brain globally. Focal brain ischemia
Focal brain ischemia occurs when a blood clot has occluded a cerebral vessel. Focal brain ischemia reduces blood flow to a specific brain region, increasing the risk of cell death to that particular area. It can be either caused by thrombosis or embolism. Global brain ischemia
Global brain ischemia occurs when blood flow to the brain is halted or drastically reduced. This is commonly caused by cardiac arrest. If sufficient circulation is restored within a short period of time, symptoms may be transient. However, if a significant amount of time passes before restoration, brain damage may be permanent. While reperfusion may be essential to protecting as much brain tissue as possible, it may also lead to reperfusion injury. Reperfusion injury is classified as the damage that ensues after restoration of blood supply to ischemic tissue.Due to different susceptibility to ischemia of various brain regions, a global brain ischemia may cause focal brain infarction. The cerebral cortex and striatum are more susceptible than the thalamus, and the thalamus in turn is more sensitive than the brainstem. Partial cerebral cortex infarction from global brain ischemia typically manifests as watershed stroke. Biomarker
Use of biomarker is one method that has been evaluated to predict the risk of stroke, diagnose stroke and its causes, predict stroke severity and outcome, and guide prevention therapy.
In addition, the use of propranolol may decrease the frequent behaviours of rage attacks.It is important for patients to take part in psychotherapy during drug therapy. In this way, many of the adverse effects of the medications, both physiological and behavioural, can be lessened or avoided entirely. Clinicians can provide useful and helpful support to patients during these psychotherapy sessions. See also
Organic mental disorder


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