National Highway Traffic Safety Administration funds WSU research on traumatic brain injury caused by motor vehicle crashes

DETROIT- Understanding the amount of stress and strain the brain can endure in a car crash before traumatic brain injury (TBI) occurs is the focus of a recent Wayne State study funded by the National Highway Traffic Safety Administration (NHTSA).

John Cavanaugh

John Cavanaugh, M.D., professor and associate chair of biomedical engineering in the College of Engineering and resident of Royal Oak, Mich., received a $336,434 grant from NHTSA to study the tolerance of nerve fibers, or axons, to high- rate loading like those seen in motor vehicle accidents. With co-investigators Chaoyang Chen, M.D., associate research professor of biomedical engineering, Srinivasu Kallakuri, research assistant in the College of Engineering and Ph.D. candidate in the Department of Anatomy and Cell Biology in the School of Medicine, the research team is focusing on traumatic axonal injury, one of the most common and devastating types of brain injury, which occurs when strain on axons causes extensive lesions to the white matter tracts in the brain.

One of the highest priorities of NHTSA is to reduce the number of deaths and injuries from TBI. The results of this research will be used to make computer models of brain injury more realistic and aid in the design of safer motor vehicles of the future. "The long-term goal of our research is to reduce the incidence of the devastating type of brain injury called traumatic axonal injury," Cavanaugh said. "We want to determine the stress, strain and strain rates that result in axonal injury and the levels at which this injury is avoided. By understanding the point at which damage occurs, we can influence the design of cars to reduce this injury."

There are already sophisticated computer models of the human brain that can measure stress, strain and strain rate in simulated crashes. Due to the inability to directly measure these in the living brain, the threshold at which axonal injury occurs is still unknown. Cavanaugh's lab has developed a one-of-a-kind in vivo model of axonal injury in a biological system in which axonal stress, strain and strain rate can be measured directly in spinal nerve roots.

Traumatic brain injuries account for more than 50,000 deaths per year in the United States. Annually, 70,000 to 90,000 TBI survivors sustain significant neurological deficits in the United States. Traumatic axonal injury is one of the major causes of unconsciousness and persistent vegetative state after head trauma. Other symptoms include lack of motor coordination and trouble with memory, concentration, attention and thinking.

"Motor vehicle crashes are the leading cause of TBI requiring hospitalization," Cavanaugh said. "Therefore, it is absolutely vital that we improve the design of cars so that fewer people will have to endure the life-altering effects of TBI. We are excited about the potential role our research can have in effecting these changes."