In the state of California, a brain herniation is defined as an injury in which the brain tissue, blood vessels and cerebrospinal fluid are pressed away or moved from their typical position inside the skull.

There are a variety of causes of brain herniation as it can occur any time something forces tissues of the brain to move. It is most commonly a side effect of tumors in the brain such as a metastatic brain tumor or a primary brain tumor. Brain herniation can also be the result of an abscess, hemorrhage, stroke, or radiation therapy. In some cases, a brain herniation can occur as the result of a traumatic injury sustained in some type of accident.

Symptoms of brain herniation include cardiac arrest, headache, lethargy, loss of consciousness, respiratory arrest or dilated pupils. Victims of brain herniation have high blood pressure, an irregular pulse, irregular breathing and a slow pulse. There will also be problems with nerve functions and brain-related reflexes depending on the section of the brain containing the herniation.

Treatment for brain herniation can vary depending on the injury. Treatment may involve a drain placed in the brain, corticosteroids, medications that help to remove excessive fluid from the body or, in the case of a patient having difficulty breathing, endotracheal intubation. Doctors may also attempt to remove any blood clots that have formed on the brain or in the skull. In some cases, a section of the skull will be removed to alleviate pressure and give the brain more room.