The US Food and Drug Administration has, for the first time, approved a blood test to help detect concussion in adults.
The Brain Trauma Indicator test measures two biomarkers: proteins known as UCH-L1 and GFAP that are released upon injury to the brain and pass through the blood-brain barrier. Elevated levels of the proteins can be detected within 15 or 20 minutes of injury. The test can be taken within 12 hours of injury, and results can be obtained within three or four hours.
Patients are currently diagnosed with concussion based on a combination of symptoms as well as imaging. However, CT scans don't always detect concussion.
"Over 90% of CT scans (for concussion) are negative. And you get 200 times the radiation of a chest X-ray. It's expensive; it's not terrific," said Hank Nordhoff, chairman and CEO of Banyan Biomarkers, maker of the new test. It can help determine whether a patient further needs a CT scan, based on a physician's concerns.
"Today's action supports the FDA's Initiative to Reduce Unnecessary Radiation Exposure from Medical Imaging -- an effort to ensure that each patient is getting the right imaging exam, at the right time, with the right radiation dose," FDA Commissioner Dr. Scott Gottlieb said in a statement Wednesday.
The test could also help reduce costs significantly. Where a CT scan can cost $800 to $1,500, Nordhoff predicts that the new test would cost closer to $150.
The test would be available to hospitals, Nordhoff said, and he hopes a handheld sideline device could be commercially available in the near future.
The FDA approved the test as part of its breakthrough devices program after evaluating a clinical study of 1,900 blood samples from people thought to have concussion or mild traumatic brain injury. The clinical trials did not include any children, though Banyan plans to include them in future studies.
When compared with a CT scan, the blood test was 97.5% as effective in detecting concussion and 99.6% effective in ruling out concussion.
The FDA believes that using this test, imaging can be avoided in at least a third of patients who are suspected of having a concussion.
According to the US Centers for Disease Control and Prevention, there were approximately 2.8 million incidents involving traumatic brain injury emergency department visits, hospitalizations and deaths in 2013.
The test looks for elevated levels of two proteins after brain injury
There are about 2.8 million concussion-related hospital visits every year