Imaging for post-concussion symptoms
Concussion is a clinical diagnosis. Imaging is used selectively — typically to exclude structural injury in the acute setting (head CT in an ER) and to evaluate persistent symptoms with brain MRI. Routine imaging for every concussion is not recommended.
When concussion does and doesn't need imaging
In the acute setting, head CT is the standard test when there are concerning features (loss of consciousness, vomiting, seizure, focal deficit, anticoagulation use, severe mechanism). Validated rules (the Canadian CT Head Rule, the New Orleans Criteria) guide ED decisions.
Outpatient brain MRI is appropriate when:
- Symptoms persist beyond 2 to 4 weeks (post-concussion syndrome)
- Neurologic exam is abnormal
- There are atypical features (worsening, focal symptoms, seizure)
- A repeat injury has occurred
Which scan for which problem
Head CT is the acute test in the ED — it's fast and detects hemorrhage and skull fracture.
Brain MRI is the right outpatient study for persistent post-concussion symptoms. It is more sensitive than CT for subtle injury including diffuse axonal injury and small contusions.
Cervical spine MRI is added when neck pain or arm symptoms persist after a head and neck injury, to evaluate disc and nerve root injury.
What the recommended scan shows
Brain MRI evaluates the entire brain for parenchymal injury, hemorrhage, infarct, and structural abnormalities. Sequences sensitive to small bleeds (susceptibility-weighted imaging) detect microhemorrhages that CT misses. Most outpatient post-concussion MRIs are normal, which is reassuring.
Common diagnoses and what they mean
Concussion (mild traumatic brain injury) — clinical diagnosis. MRI is typically normal.
Post-concussion syndrome — persistent headache, dizziness, cognitive symptoms, sleep disturbance beyond expected recovery window. Imaging usually normal.
Cerebral contusion — focal brain bruise; visible on MRI better than CT.
Subdural or epidural hematoma — collection between the skull and brain; usually identified acutely on head CT.
Diffuse axonal injury — shearing injury from rotational forces; best seen on MRI with sensitive sequences.
What happens after results
Most outpatient post-concussion MRIs are normal. Management of post-concussion syndrome is multidisciplinary — symptom-targeted treatment, vestibular rehabilitation for dizziness, gradual return to activity, and neurology referral for persistent symptoms.
How to get the scan at Precise
Bring your physician's order. Brain MRI takes about 30 to 40 minutes and most studies are performed without contrast. See our brain MRI page for locations.
Frequently asked questions
How to schedule at Precise
Once you and your physician decide imaging is the right next step, scheduling is quick. Bring your prescription, photo ID, and insurance card.
Condition overview
Learn more about the specific conditions associated with this symptom — what imaging is used, what it shows, and how to schedule at Precise.
Find imaging near you
Precise Imaging has locations across California with same-day scheduling, board-certified radiologist reads, and transparent pricing.