The University of Rochester Medical Center received $1.5 million to develop a blood test for concussions by isolating proteins that can predict memory loss, chronic headaches or other neurological problems.
At least one million Americans seek treatment for head injuries each year. However, many people initially assume their injury is mild and do not visit a doctor until after they experience cognitive difficulties. Having a rapid test that could be administered on sports fields, at the scene of automobile accidents or in combat situations would give medical personnel a head start, and offer clues about the extent of the brain injury.
“We are discovering that concussions are not benign, even if you only have one in a lifetime and it's relatively mild,” said principal investigator Jeffrey J. Bazarian, M.D., M.P.H., associate professor of Emergency Medicine and Neurology. “The latest research shows that mild or moderate head injuries might be a risk factor for early-onset dementia or Alzheimer's disease. This makes proper, timely diagnosis very important.”
A blood test would help doctors diagnose axonal injury, a type of brain injury that often occurs after a concussion but does not show up on a CT scan of the brain. In fact, a CT scan can appear normal in patients who suffer from lasting neurological defects due to axonal injuries, Bazarian said.
Diagnosis of axonal injury is difficult because CT scans are designed to detect bleeding in the brain, and not more subtle injury to neurons, the cells responsible for cognitive functioning. Axons make up the bulk of the neuron's structure. Axons travel in clusters, providing a connection to different areas of the brain through delicate, spaghetti-like strands. When axon fibers are stretched or strained, they stop working and the entire cell dies. Blows to the head, falls, or sudden deceleration from motor vehicle accidents can cause axonal injuries.
In a pilot study, Bazarian investigated whether a new type of brain scan called Diffusion Tensor Imaging (DTI), a dynamic form of the well-known MRI, could detect axonal damage from a minor injury. He studied the DTI scans of six people with mild concussions, and compared them to six scans of non-injured brains. Indeed, the DTI showed subtle axon swelling, which is known to occur when the axons are over-stretched. The axonal swelling correlated with the patients who were having trouble processing information or remembering things as well as before the injury.
Now, with the latest funding from the National Institutes of Health, Bazarian will use DTI technology to aid in a search for biomarkers that indicate axonal damage.
Researchers will conduct a clinical study by enrolling 37 adults, ages 18 to 65, who seek emergency treatment for head injuries. A control group will consist of 37 patients who seek treatment for orthopedic injuries such as sprained ankles or broken wrists. All patients will undergo a DTI brain scan and provide blood samples.