WSU Biomedical engineers embark on new traumatic brain injury study

DETROIT - A team of Wayne State University (WSU) biomedical engineers has embarked on a unique four-year study of the biomechanical basis of brain trauma. They anticipate the findings will lead to more effective injury prevention strategies for brain injury.

Supported by a new $1.3 million grant from the National Institutes of Health, the researchers will track and map the response of laboratory-induced trauma to shed light on the precise mechanical events that lead to brain injury at the axonal and cellular levels.

About 50,000 Americans die each year after sustaining a traumatic brain injury (TBI). The majority of the 1.5 million injuries per year are the result of auto crashes, followed by sports accidents, falls and violence. For many victims there is no effective prevention or treatment.

"At Wayne State, we're uniquely positioned to study and understand the mechanisms of severe brain trauma because of our expertise in impact biomechanics and our leading position in the development of world class computer models of the human brain," said Liying Zhang, associate research professor in the Department of Biomedical Engineering and the principal investigator on the project. An expert in injury biomechanics and neurotrauma, Zhang is one of only a few researchers in the world specialized in computer modeling of head protection using finite element techniques.

"Brain injuries can be prevented with available technologies if we can understand the mechanical conditions that produce the injury," said Zhang. "The standards that exist today for crash safety are based on data more than four decades old. The standards need to be updated if we are going to make significant inroads into preventing brain injuries."

The critical missing piece is a reliable predictor of the stresses and strains that produce these injuries. Once mapped, protective equipment such as helmets and airbags can be designed to prevent these injuries. The NIH study will examine how brain tissues respond to mechanical insult at the cellular level and the stresses and strains that cause brain injury.

Zhang will work with WSU Professor of Biomedical Engineering John Cavanaugh, M.D., an expert in impact biomechanics and neurophysiology. Cavanaugh's lab has performed extensive research in axonal injury, concussion and spinal disorders.

While researchers elsewhere study the mechanics of the impact and response of the brain to injury, or analyze the cellular changes in the brain using histopathologic techniques, the Wayne State team is uniquely capable of reconstructing the injury process dynamically by integrating both approaches.

"This award from the NIH is a testament to the impressive and important research being done in WSU's biomedical engineering department," Gloria Heppner, associate vice president for research at WSU. "This project can make a major impact on preventing and treating major head injuries."

Engineering Dean Ralph Kummler said, "Our Biomedical Engineering Department has been a world wide leader in the design for prevention of injuries in general and Dr. Zhang and Dr. Cavanaugh have been leaders in the study of brain injury. This new NIH grant will allow them to translate years of experimental research into computer analysis and design tools that will save lives and enhance the lives of thousands of accident and battlefield victims. It is an outstanding example of the leading edge research being done in BME."

For more than six years, Zhang and her colleagues have been studying the mechanism of concussions sustained by professional football players in the National Football League. The computer models were developed from many decades of head injury research at Wayne State. The tissue level injury thresholds the researchers obtained for mild traumatic brain injury enhanced the utility of their computer models. However, the direct correlation of in vivo neural injury with local mechanical response in the brain has not been directly demonstrated. This NIH supported in vivo quantification will be carried out in collaboration with Dr. Cavanaugh's laboratory.

"Computer modeling of injury allows us to explore the complex modes of deformation in brain tissue that stretch the axons, trigger neurochemical cascades and lead to cell death," Zhang said. "One of our goals is to identify and quantify the thresholds required that trigger this cascade. We know that the mechanical behavior of neural tissue does not vary significantly from one species to another. So the threshold levels developed in this study can be directly translated to our human head models and improve their predictive power."