"This stuff is over before you have any chance to react and probably before you even knew it happened to you," Taylor said. Humans' fastest reaction times as teenagers are 75-100 milliseconds.
Ford says levels of energy transmitted into the brain by a blast wave "could be part of the injury mechanism associated with TBI and the mechanism by which it happens may not be mitigated by traditional methods of protecting the head with a helmet."
At Sandia, researchers created a computer model of a man's head and neck. The model includes the jaw another first in TBI research because a lot of blasts come from improvised explosive devices (IEDs) at ground level, sending waves traveling at the speed of sound through the jaw and facial structure before they reach the brain, Taylor said.
Sandia's team used the National Library of Medicine's Visible Human Project, which was established in 1989 to build a digital image library of volumetric data representing complete, normal adult male and female anatomy.
Using images of the male, whose age was close to that of most military personnel, Taylor, with Ford as a medical consultant, created geometric models of the seven tissue types in the human head scalp, bone, white and gray brain matter, membranes, cerebral spinal fluid, and air spaces. Over a year, they catalogued each of the tissue types seen in about 300 "slices" of the cadaver's head, dividing what they saw into one-millimeter cubes and assigning each a tissue type for the computer simulation.
Taylor also imported digitally processed, computed tomography (CT) scans of various helmet designs into the simulations to assess the protective merits of each against blast loading.
In a typical blast simulation, 96 processors on Sandia's Red Sky
|Contact: Heather Clark|
DOE/Sandia National Laboratories