Concussion Workup

Updated: Jan 06, 2023
  • Author: David T Bernhardt, MD; Chief Editor: Craig C Young, MD  more...
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Imaging for Concussion

It is important to be cognizant of the fact that although the following studies may be useful in the evaluation of head trauma, they will be negative for a concussion with no other injury.

CT scanning

In an emergency department-based study, the percentage of abnormal CT scans in adult patients increased from 13% for patients with a perfect GCS score to 37% for those with a GCS score of 13.

In a different study that assessed 712 patients with LOC or amnesia and a perfect GCS, the rate of abnormal CT scans was 9%, with less than 1% requiring surgical intervention. [59]

Indications for ordering a CT scan include focal neurologic examination findings, signs or symptoms of increased intracranial pressure, GCS score less than 15, and seizures related to trauma. Some authors suggest that any athlete with loss LOC (grade 3 concussion) should have a CT scan obtained. [60] This area is controversial. Athletes with a brief LOC are at no higher risk for long-term neurologic sequelae, and indications for imaging should not differ from those listed above.

CT scanning continues to be the imaging study of choice in evaluating an acute head injury. Better imaging of an acute hemorrhage, speed of the study, and improved ability to monitor the patient are the reasons for using CT scanning rather than magnetic resonance imaging (MRI).


MRI is the imaging study of choice for patients who have prolonged symptoms (> 7 d) or for a late change in an individual's neurologic signs or symptoms.

MRI offers a more detailed examination and possibly detects more subtle findings.

Delayed or slowly developing bleeds may be easier to detect on MRI.

A study by Strauss et al identified early diffusion tensor imaging (DTI) biomarkers of mild traumatic brain injury that significantly relate to outcomes at 1 year following injury. The study found that abnormally high fractional anisotropy is significantly associated with better outcomes and might represent an imaging correlate of postinjury compensatory processes. [61, 62]

Neuropsychologic testing

Detailed neuropsychologic testing is employed more often at the professional level and in research in athletes with MTBI.

When evaluating an athlete's performance on the neuropsychologic tests, it is best to compare results with the athlete's previous tests.

The National Hockey League (NHL), National Football League (NFL), Major League Baseball (MLB) as well as many college teams are utilizing limited neuropsychologic testing to document the possible prolonged effects of presumed minor head injuries and to assist the clinician in determining possible retirement issues.

Neuropsychologic testing is indicated in cases of complex concussions. [47]

Although positron emission tomography (PET) scanning and functional MRIs (fMRIs) may be used, their clinical application in most cases of MTBI is uncertain. [8, 9, 10]


Laboratory Studies

A study by Papa et al evaluated the serum levels of two biomarkers, glial fibrillary acidic protein (GFAP) and ubiquitin C-terminal hydrolase (UCH-L1) that show promise for clinical usefulness in suspected traumatic brain injury (TBI) and concussion. The study found that GFAP performed consistently in detecting MMTBI, CT lesions, and neurosurgical intervention across 7 days and that UCH-L1 performed best in the early postinjury period. [63, 64]