EEG After Head Injury & Concussion
Post-traumatic seizure workup, persistent-symptom assessment, and informed return-to-activity decisions. Same-day expert reporting.
Why EEG After Head Injury?
Most head injuries do not require an EEG. When EEG is indicated, it answers specific questions about seizure risk, persistent symptoms, or whether something else is going on alongside the injury.
Post-Traumatic Seizure Workup
If you have had a witnessed seizure after the injury, or symptoms suggestive of subtle seizures (staring spells, episodes of confusion, unusual movements), EEG looks for epileptiform discharges that support the diagnosis and guide treatment.
Persistent or Atypical Symptoms
When symptoms continue beyond the expected concussion recovery window, or do not fit the usual post-concussion pattern, EEG helps look for focal cortical disturbance or subclinical seizure activity that could explain ongoing problems.
Risk Assessment in Moderate–Severe TBI
After moderate or severe traumatic brain injury, the risk of developing post-traumatic epilepsy is elevated — particularly with skull fracture, intracerebral haemorrhage, or prolonged loss of consciousness. EEG contributes to assessing that risk.
An uncomplicated concussion in the absence of seizures does not need an EEG. The decision to order one is driven by specific clinical features — not by the head injury alone. Your neurologist will discuss whether EEG is likely to add useful information in your case.
When EEG Is Indicated After Head Injury
These are the scenarios where EEG adds the most value after a head injury, concussion, or traumatic brain injury.
Whether acute (within the first week) or late (occurring weeks to months later).
Staring spells, sudden unexplained confusion, automatisms, or brief episodes of unresponsiveness.
Particularly with skull fracture, intracerebral haemorrhage, or prolonged loss of consciousness.
Ongoing cognitive slowing, headache, or sleep disturbance that does not fit typical post-concussion syndrome.
Symptoms that do not fit the usual post-concussion pattern or evolve over time.
Selected cases where EEG findings help inform return-to-sport, return-to-work, or driving discussions.
Significantly elevated post-traumatic epilepsy risk warrants baseline and follow-up evaluation.
Occasionally requested before starting medications that may lower seizure threshold or affect cortical excitability.
How the Workup Is Structured
EEG is one part of a broader assessment. Timing and type of recording depend on the clinical question.
Clinical assessment first
Detailed history of the injury and the symptoms, neurological examination, review of any imaging already done. This decides whether EEG is the right next step or whether other investigations are needed first.
Routine EEG — about 40 minutes
First-line recording. Captures awake brain activity with hyperventilation and photic stimulation. Looks for focal slowing, epileptiform discharges, or other patterns that point to seizures or focal cortical disturbance.
Sleep-deprived EEG when needed
If the routine EEG is normal but clinical suspicion of post-traumatic epilepsy remains high, a sleep-deprived recording significantly increases the chance of detecting epileptiform activity. Often the next step in workup of unexplained post-injury seizure-like episodes.
Integration with imaging and clinical picture
EEG findings are interpreted alongside CT or MRI and the clinical context. A normal EEG does not rule out future seizures, and an abnormal EEG must always be interpreted against the symptoms and history. Your neurologist puts the picture together.
Same-day report back to your GP
The recording is analysed the same day. Your neurologist's report is sent to your GP that evening.
Frequently Asked Questions
Do I need an EEG after every head injury?
No. The majority of head injuries — including uncomplicated concussion — do not need an EEG. EEG is reserved for specific situations: a witnessed seizure after the injury, suspected ongoing subclinical seizures, persistent neurological symptoms not explained by post-concussion syndrome, or moderate-to-severe traumatic brain injury where post-traumatic epilepsy risk is elevated.
Can EEG diagnose post-concussion syndrome?
Post-concussion syndrome is a clinical diagnosis. Routine EEG is often normal in post-concussion syndrome and is not used to confirm it. EEG's role is to rule out other contributors — particularly subtle ongoing seizure activity or focal cortical disturbance — rather than to make the diagnosis itself.
What is post-traumatic epilepsy and how does EEG help?
Post-traumatic epilepsy is recurrent unprovoked seizures occurring after a head injury, with risk strongly related to injury severity. EEG can detect epileptiform discharges that support the diagnosis, classify the seizure type, and guide which anti-seizure medication is most appropriate. A normal EEG does not rule it out and may need to be repeated or sleep-deprived if clinical suspicion remains high.
When is the best time to do an EEG after a head injury?
Timing depends on the clinical question. If there is a suspected ongoing seizure or altered consciousness, EEG is done urgently. For workup of post-traumatic epilepsy risk in someone clinically stable, EEG is usually arranged after the acute phase has settled — typically several weeks to a few months after the injury — so the recording reflects ongoing brain activity rather than transient acute injury effects.
Can EEG help with return-to-play or return-to-work decisions after concussion?
EEG plays a supportive role in selected cases — particularly where there has been a post-injury seizure or persistent atypical symptoms. Return-to-play and return-to-work decisions are primarily clinical and based on symptom resolution, cognitive recovery, and graded return protocols. EEG is one piece of information your neurologist may use, not the deciding factor.
Book Expert EEG After Head Injury
Same-day reporting. Specialist post-traumatic seizure workup and persistent-symptom assessment. Bondi Junction.