How common is epilepsy after head trauma?
The risk of developing epilepsy is related to the severity of injury. In persons with open head injuries (when the coverings of brain are penetrated) about 40% develop epilepsy later on in life as compared to only 5% of those with closed head injury. Other factors that predispose to development of epilepsy in persons with head injury are associated bleeding in the brain, occurrence of seizures within the first week of injury and prolonged period of unconsciousness after the injury. It has been estimated that almost half the patients with epilepsy secondary to head trauma develop it within the first year of injury and about 75% develop within two years. In some series it has been estimated that almost 10 – 15% of all cases of epilepsy are secondary to head trauma.
