Researchers from Washington University in St. Louis and the University’s Barnes-Jewish Hospital devised a new imaging technique to visualize brain deformation during acceleration-deceleration episodes such as those experienced by athletes playing contact sports like rugby:
What they’ve done is use a technique originally developed to measure cardiac deformation to image deformation in human subjects during repeated mild head decelerations. Picture, if you will, a mangled quarterback’s occipital bone banging the ground, then rebounding. The researchers have mimicked that very motion with humans on a far milder, gentler, smaller scale and captured the movement inside the brain by magnetic resonance imaging (MRI).
Philip Bayly, Ph.D., Lilyan and E. Lisle Hughes Professor in Engineering, Guy Genin, Ph.D., assistant professor of mechanical engineering, and Eric Leuthardt, MD, formerly a resident at Barnes-Jewish Hospital, now at the University of Washington, tested seven subjects in an MRI and gathered data that show that the brain, connected to the skull by numerous vessels, membranes and nerves at the base, tries to pull away from all those attachments, leading to a significant deformation of the front of the brain.
According to Genin, the subjects are placed in the soft netting of a head guide, and are asked to raise and lower their heads about an inch inside an MRI machine. The process is repeated several times as the MRI pieces together a complete movie of the brain’s response to these skull motions.
“Phil (Bayly) has developed a set of state-of-the-art hardware and software to synchronize and analyze all of these measurements,” said Genin. “The systems he has developed will allow us to explore a broad range of questions critical to understanding mild traumatic brain injury.”
“It’s an interesting thing that in many occipital impact injuries, people often find the greatest injury in the front of the brain,” Bayly said. “That has been a puzzle for a long time and there have been numerous different explanations for it. What we see with the MRI is quite a bit of mechanical deformation in the front of the brain when the skull is hit from the rear. It seems to be because the brain is trying to pull away from some constraints in the front of the brain.”
More from the Washington University press office…