Traumatic brain injury has become the signature war wound for soldiers serving in Iraq and Afghanistan--and new research suggests that soldiers may not be adequately protected against the explosions that cause these injuries. By modeling how blast waves propagate through a soldier's head, an MIT research group found that current combat helmets don't offer much protection, because the blast waves from improvised explosive devices (IEDs) can enter the skull through the face.
"There's a passageway through those soft tissues directly into the brain tissue, without having to go through bone or anything hard," said Raul Radovitzky, an aeronautical engineer at the Massachusetts Institute of Technology. [LiveScience]
, which was published online in Proceedings of the National Academy of Sciences, the researchers created their own computer model based on a real person's brain scans; what they found actually contradicted findings from earlier, rougher models. A previous study
, published in August, suggested that current helmet design actually increases brain injuries during an explosion by focusing and intensifying the blast waves inside the helmet.
"The existing Advanced Combat Helmet... does not worsen the negative effects of a blast wave--does not enhance the energy of the blast--as has been previously suggested," Dr Radovitzky told BBC News. "But we also find that it doesn't really help much; it doesn't mitigate the blast wave significantly." [BBC News]
The authors suggested a new design with a polycarbonate shield that comes down over the face, which would deflect the force of the blast awat from the face's soft tissues. The shield would resemble the clear plastic visor used in motorcycle helmets.
With a shield in place, "you actually do mitigate the effects of the blast quite significantly," said Raul Radovitzky [LA Times]
Changing the helmets for an entire army isn't so easy, though, especially when other factors come into account--like the limited visibility that might come with a face shield. Says Radovitzky:
"There are of course many other aspects of putting a face shield on a soldier's helmet that need to be taken into account, like how you would affect the situational awareness of the soldier, how they can operate without being hindered by the device." [BBC News]
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Image: Flickr/The U.S. Army