Edema is a medical term for swelling. When there is swelling on the brain, it is termed cerebral edema or brain edema, which results in increased pressure inside the skull. The increases in pressure, termed intracranial pressure, can prevent blood flow to parts of the brain or it can block other fluids from dissipating. Cerebral edema can result in damage or death of brain cells.
Infection
Meningitis is an example of an infection that can cause cerebral edema. Meningitis causes the "dura," which cover and protect the brain, to become inflamed and can be caused by bacteria, some medications or viruses, notes the Meningitis Research Foundation. Toxoplasmosis is another infection that can result in cerebral edema. It is caused by a parasite and usually affects fetuses or young infants, according to the Centers for Disease Control and Prevention. Encephalitis is an infection that causes the brain itself to become inflamed, notes MayoClinic.com, and can result in cerebral edema.
Stroke
Ischemic strokes are caused by a blocked blood vessel and results in cell death, notes MayoClinic.com. The body responds to the necrotic cells and sends "help," which results in swelling of the area. Strokes can also be caused by hemorrhages, where blood leaks out of a blood vessel and the blood builds up and increases intracranial pressure and edema, according to MayoClinic.com. Hemorrhages can also be caused by injury.
Injury
Common injuries that result in edema are falls, direct blows or vehicle accidents that result in head injury, notes MedlinePlus. Initially, these types of injuries can cause brain tissue to swell, and the body's response to injury can also result in swelling. Excessive swelling can prevent the cerebrospinal fluid from leaving the brain, increasing the pressure even more.
Tumors
Tumor growth can cause increased pressure on the brain. Additionally, tumors can block cerebrospinal fluid from leaving the brain and the growth of new blood vessels to feed the tumor can do the same thing, notes The American Brain Tumor Association. Furthermore, it is possible that the treatment used to address the tumor can contribute to brain swelling, according to The American Brain Tumor Association.
High Altitude
Although the mechanism is unknown, cerebral edema is more likely to occur at altitudes above 8,000 feet. Acute mountain sickness, or AMS, in its late stages, is associated with cerebral and pulmonary edema, according to MedlinePlus.
