Just one concussion can cause long-term structural damage to the brain, according to a new study.
Researchers used 3-D MRI to examine the volume of gray and white brain matter in 19 concussion patients one year after their injury, and in 12 people who had not suffered a concussion. The scans revealed measurable losses of gray and white matter (brain atrophy) in the concussion patients, according to the study, which was published online March 12 in the journal Radiology.
The finding is the first of its kind and shows that brain atrophy occurs not only in people who have suffered severe brain injuries, but also in those who have had just one concussion, said Dr. Yvonne Lui, neuroradiology section chief and assistant professor of radiology at the NYU Langone School of Medicine, in New York City.
"This study confirms what we have long suspected," Lui said in a journal news release. "After [concussion], there is true structural injury to the brain, even though we don't see much on routine clinical imaging."
Lui said this means that changes in brain structure may be the cause of long-term symptoms in patients who have suffered a concussion.
"It is important for patients who have had a concussion to be evaluated by a physician," Lui said. "If patients continue to have symptoms after concussion, they should follow up with their physician before engaging in high-risk activities such as contact sports."
Following a concussion, some people briefly lose consciousness. Other symptoms include headache, dizziness, memory loss, attention problems, depression and anxiety. Some of these symptoms may last for months or even years.
Previous research has shown that 10 percent to 20 percent of concussion patients continue to experience symptoms more than a year after their head injury.
Although the study tied having a single concussion to higher risk of long-term brain injury, it did not establish a cause-and-effect relationship.