Brain Edema - Causes and Symptoms

Definition

Cerebral edema is a collection of fluid that causes a rapid increase in brain volume. At the base, there may be two different mechanisms: the extravasation of plasma from the capillaries (vasogenic edema), or, more rarely, an accumulation of fluids within the nerve cells themselves (neurogenic edema).

Since the skull is rigid, cerebral edema causes intracranial hypertension, which results in symptoms such as severe headache, vomiting, loss of vision, confusion, memory disorders and coma. Furthermore, the collection of liquids compresses the tissues, damaging them and limiting the supply of oxygen and blood.

Cerebral edema can be caused by head trauma, tumors, circulatory disorders, inflammation, anoxia, hypertensive encephalopathy and ischemia. It can also occur following an infection (eg meningitis and encephalitis), intoxication (eg paracetamol poisoning or abuse of opiate drugs, such as morphine) or some metabolic alterations (eg diabetic ketoacidosis).

Other possible causes include allergic reactions, cardiac arrest, Reye's syndrome, hepatic encephalopathy and altitude sickness.