Soldiers may soon be able to avoid an all too common injury associated with modern warfare, if a new helmet and visor design make it to the field.
In Iraq and Afghanistan, the most common military injury is known as "blast-induced traumatic brain injury." Some 130,000 U.S. service members deployed in Iraq and Afghanistan have sustained traumatic brain injuries (TBIs) as a result of explosions, according to the Department of Defense, which can result in concussions, long-term brain damage, and death. (And that number could be even higher.)
So a team of researchers at MIT have been using a sophisticated computer simulator to investigate the effects of both the Advanced Combat Helmet (ACH) and a face shield on that helmet.
Perhaps most surprising is their finding that the ACH itself, in simulation, barely mitigates the effects of blasts. Using both the helmet and the face shield, however, does delay the transmission of blast wave stresses to the head, and could prove to be a more effective strategy for dealing with these injuries.
"There is a community studying this problem that is in dire need of this technology," says Raul Radovitzky, an associate director of MIT's Institute for Soldier Nanotechnologies, in a news release. Radovitzky is releasing the computer code for the creation of the models to the public this week, alongside the publication of the study's findings in the Proceedings of the National Academy of Sciences. (For the code, e-mail firstname.lastname@example.org.)
To create the models, the MIT team worked with David Moore, a neurologist at the Defense and Veterans Brain Injury Center at Walter Reed Army Medical Center, who uses magnetic resonance imaging to model features of the head. The researchers added data from other studies of how pigs' brain tissue responds to mechanical events, such as blasts, as well as details about the explosive type, mass, and location relative to the target.
The result: unprecedented anatomical detail of the skull, sinuses, cerebrospinal fluid, and layers of gray and white matter, not to mention the characteristics of the blast wave itself.
"This would be difficult to test in any useful way without using models," says Joseph Rosen, a professor of surgery at the Dartmouth-Hitchcock Medical Center who, though not involved in this research, chaired a Department of Defense science panel analyzing blast injuries on wounded soldiers. "What is ultimately important is the impact of the blast on the face, skull, and brain."
While Radovitzky at MIT sees potential in the face shield for the civilian population as well (think sports injuries and car crashes), widespread adoption beyond combat zones might be tricky. That helmet-in-the-car scene in "Benny & Joon" comes to mind.
A final note. This study compared the effects of blasts on the head without a helmet, with a helmet, and with a helmet and face shield, but the source of the blast always came from the front. So the actual benefit of the face shield may only come into play in very specific angles, when the shield itself is between the blast and the head.