Research news: July 2011
N Engl J Med2011;364:2091-100
It is unclear whether explosion blasts can damage the brain in the absence of a visible head wound. Lasting cognitive effects are often seen after exposure to mild or moderate blasts, although this is usually not accompanied by any structural brain damage visible with computed tomography or magnetic resonance imaging. Diffusion tensor imaging, however, an advanced form of magnetic resonance imaging, can detect more subtle brain defects in the form of axonal damage.
In 63 US military personnel who had a clinical diagnosis of mild uncomplicated traumatic brain injury, the advanced imaging method showed more axonal damage than was seen in the control group—21 military personnel exposed to blasts and other injuries but with no clinical diagnosis of traumatic brain injury. Axonal damage was seen in the regions of the brain that computer simulations had previously indicated would most likely be injured in blasts. These regions