Using an advanced imaging technique, researchers were able to predict which concussion patients would make a full recovery within one year, according to a new study by Albert Einstein College of Medicine and Montefiore Health System.
The findings shed light on the brain’s mechanisms for repairing or compensating for concussion injuries — information that could help researchers develop effective therapies.
“Our study presents for the first time a precision approach to harness imaging at the time of concussion to forecast outcome a year later,” said study leader Michael L. Lipton, M.D., Ph.D., associate director of the Gruss Magnetic Resonance Research Center (MRRC) at Einstein and director of MRI services at Montefiore.
“While we still lack effective treatments, we now have a better understanding of the neurological mechanisms that underlie a favorable response to concussion, which opens a new window on how to look at therapies and to measure their effectiveness.”
Currently, there are no objective biomarkers or tests for concussions, and doctors must rely on symptoms alone for a diagnosis.
Concussion symptoms vary widely and may be immediate and fleeting, indefinite, or in some cases, even delayed for days or weeks after injury. Symptoms may include seizures, trouble sleeping, decreased coordination, repeated vomiting or nausea, confusion, and slurred speech.
“While most people think of concussions as a mild and short-lived injury, 15 to 30 percent of patients are left with symptoms that persist indefinitely,” said Sara Strauss, M.D., the study’s lead author and resident in the department of radiology at Montefiore.
“Until now, we haven’t had a reliable way to differentiate in advance those who may be burdened long-term and those who would have a complete recovery.”
In a previous study, the researchers found that an advanced form of MRI, called diffusion tensor imaging (DTI), was able to detect concussion-related damage to axons (the nerve fibers that constitute the brain’s white matter).
It does so by “seeing” the movement of water molecules along axons, which allows researchers to measure the uniformity of water movement (called fractional anisotropy, or FA) throughout the brain.
Finding a low FA brain region, for example, indicates structural damage that has disrupted water movement in that area. In contrast, abnormally high FA may indicate where the brain has responded favorably to injury, perhaps by more efficiently connecting axons or by remyelinating injured tissue
For the new study, the researchers wanted to know whether brain abnormalities identified on DTI of individual concussion patients could successfully determine which patients would eventually recover.
The study involved 39 patients who had been diagnosed with mild TBI by an emergency room physician within 16 days of the initial injury as well as 40 healthy controls. The DTI image of each patient was compared with all images of the health control group to see where patients’ brains were abnormal.
The findings reveal that having a greater volume of abnormally high FA white-matter areas (perhaps indicating good compensation for concussion damage) was associated with better outcomes one year later.
“Being able to predict which patients have a good or bad prognosis has tremendous implications for discovering and evaluating treatments for concussion,” said Lipton.
“Developing an effective intervention requires first identifying the people who need it. Seventy to 85 percent of concussion patients get better by themselves, which makes it difficult to learn whether any treatment is actually helping. Our imaging technique allows researchers to test potential therapies on those concussion patients who can truly benefit from them.”
The study is published online in the American Journal of Neuroradiology.
PHOTO CREDIT: Gordon Kindlmann at the Scientific Computing and Imaging Institute, University of Utah, and Andrew Alexander, W.M. Keck Laboratory for Functional Brain Imaging and Behaviour, University of Wisconsin .