According to the Epilepsy Foundation and Brain Injury Association a Traumatic Brain Injury (TBI) is a well recognized cause of seizures and epilepsy.
Per the Epilepsy Foundation:
Seizures can occur early ( within the first week of the brain injury), or late ( more than a week after brain injury). Seizures which occur early after a traumatic brain injury are felt to be a symptom of the recent injury. Seizures which occur in the late period after TBI are more likely to recur and result in epilepsy.
Early seizures in TBI
Approximately 1 in 10 people (10%) will experience an early seizure after TBI
50% of early seizures occur during the first 24 hours following TBI
25% of early seizures occur during the first hour following TBI
Most very early seizures (within 24 hours of injury) are generalized tonic clonic seizures
About 1 in 10 people will develop status epilepticus in the early period after a TBI
Younger children are at highest risk for early post traumatic seizures and status epilepticus
experience an early seizure.
People who have head injuries that are more serious (examples: car accidents, fall from height, military blast injury), cause brain swelling or blood on the outside of the brain (subdural hemorrhage), or involve the brain being penetrated by a foreign object (example: bullet, combat injuries), or are accompanied by an extended period with loss of consciousness (>30 minutes) are more likely to have early seizures. One in four people who suffer from bleeding in the brain (intracerebral hematoma) requiring surgery or a skull fracture that compresses or injures brain tissue
In some cases, even if a head injury is “mild” and a person has no evidence of injury to the brain on brain imaging with CT or MRI, a seizure may still occur
EEG changes may or may not be present in the immediate period after a head injury
If markers of seizures on EEG early after TBI this may mean a person is more likely to develop epilepsy
People with early seizures after a brain trauma are at higher risk for developing post-traumatic epilepsy
What Are Late Seizures?
Seizures which occur more than a week after a traumatic brain injury are considered late seizures. Most often when this happens, it is because there has been more serious injury to brain cells and the chemical environment around the cells has also changed. Late seizures are more likely to lead to the complication of post-traumatic epilepsy.
Resources:
Epilepsy Foundation
Brain Injury Association