Thought Leadership in Action

The brain’s soft, sensitive tissues float in a cushioning fluid, protected inside the hard and sturdy skull. However, a swift blow to the head or violent shaking of the body can over-ride the skull’s protection and lead to the usually mild type of brain injury known as a concussion. The Centers for Disease Control (CDC) notes that each year about 1.7 million children and adults in the U.S. suffer traumatic brain injuries (TBI) -- and the vast majority of these TBIs are concussions.

“Although concussions are considered to be a mild brain injury, they need to be taken seriously. They should not be treated as minor injuries that quickly resolve,” Dr. Beth Ansel, an expert on rehabilitation research at the National Institutes of Health (NIH), said in a media statement.

While it is true that with proper care, which consists primarily of rest, most people fully recover after suffering a concussion, Dr. Ansel added that “in some cases, a concussion can have a lasting effect on thinking, attention, learning and memory.”

Unfortunately, diagnosing concussions isn’t always easy and symptoms can be initially mistaken for other problems, delaying treatment. However, new inexpensive blood tests are on the horizon that promise to make diagnosing concussions, and even predicting the severity of these brain injuries, much simpler and quicker.

Diagnosing Concussions

While a car crash, sports injury or bad fall are the most frequent and obvious causes, concussions can also sometimes result from what seems to be a minor “bump on the noggin” – such as walking into a cabinet door or having a box topple from a shelf onto your head.

So how does a person know if they’ve suffered a concussion? According to the Mayo Clinic, symptoms can be obvious and include a loss of consciousness, seeing “stars,” an ongoing dazed feeling and amnesia around the traumatic event. But you can also experience headaches, neck pain, nausea, ringing in the ears, dizziness, or tiredness that can be mistaken for another problem, such as a virus or migraine. Adding to a sometimes confusing picture of a concussion, symptoms may not develop until days or even weeks after the head injury.

Currently, diagnosis of a concussion depends primarily on a neurological exam by a physician who checks reflexes, memory, vision, hearing and coordination. In some cases, a cranial computerized tomography (CT) scan is ordered to assess the brain right after injury and check for skull fractures and internal bleeding.

Over the past few years, however, scientists from multiple research centers have been studying blood tests that appear to accurately and immediately diagnose concussions.

Diagnosing Concussions With a Drop of Blood

Recently, the National Football League (NFL) acknowledged that many of its ex-players suffer from chronic traumatic encephalopathy (CTE), a serious brain condition linked to repeated concussions. CTE, which causes memory loss and other neurological problems, is an extreme example of the potential dangers of concussions. However, the concern in the sports world about these brain injuries has spurred on research that could potentially revolutionize diagnosing all concussions.

One such example is a brain protein, dubbed S100B that has been found to increase in the bloodstream after intense exertion – but also spike after a blow to the head. So University of Rochester scientists investigated whether it would be possible to distinguish the two circumstances in order to quickly find signs of a concussion using a blood test to measure the protein.

In a study involving 46 athletes, baselines of S100B levels in the blood were measured before they began their game season. After strenuous exercise, the research subjects were tested again and their S100B levels were found to be slightly higher. But during the athletes’ competitive season, S100B blood tests performed on the research subjects who sustained head blows during games showed those players with significantly elevated levels of the protein went on to have clinically diagnosed concussions. In fact, the researchers concluded that a rise in S100B of more than 45 percent in the blood was basically a positive test for a concussion.

These findings, published in the medical journal PLOS ONE, suggest that it may be possible to use a simple blood test at a sports game to identify which players who have experienced head traumas need to be monitored and treated for concussions in order to reduce their chances of more permanent and lasting damage. It also suggests that this knowledge about S100B could result in quick blood tests being used in the not-too-distant future to pinpoint concussions in the general population.

Blood Test for Concussion Complications

Current neurological evaluations used to diagnose a concussion are not able to determine the extent of the TBI, or whether the injured person will be among the 15 to 30 percent who experience significant, persistent cognitive deficits, such as deficits in working memory and the ability to switch or balance multiple thoughts. However, researchers in the Perelman School of Medicine at the University of Pennsylvania, in conjunction with colleagues at Baylor College of Medicine, have discovered that a new blood biomarker can correctly predict which people with concussions will likely develop persistent cognitive dysfunction.

This research, published in Frontiers in Neurology, found that a protein, called calpain-cleaved αII-spectrin N-terminal fragment (SNTF), correlates with the amount of damage to brain tissue – and it was twice as high in a subset of patients following a concussion who developed memory and other problems after their TBI. The test could eventually be used to identify those at increased risk for persistent problems following a concussion before they return to sports, military or work duties.

"New tests that are fast, simple and reliable are badly needed to predict who may experience long-term effects from concussions, and as new treatments are developed in the future, to identify who should be eligible for clinical trials or early interventions," said lead author Robert Siman, PhD, research professor of Neurosurgery at Penn. "Measuring the blood levels of SNTF on the day of a brain injury may help to identify the subset of concussed patients who are at risk of persistent disability."