Blast-Induced Brain Injuries from Iraq and Afghanistan
What has been called the "signature wound" of the wars in Iraq and Afghanistan— the mild brain damage troops suffer from a roadside bomb — might be so unique in its destruction that it could be a newly discovered disease, scientists say.
Army field studies have shown that more than 10% of troops in Iraq and Afghanistan have suffered at least one concussion or brain injury, the vast majority of those from exposure to a homemade bomb or improvised explosive device. Five percent to 15% of mild TBI patients develop lasting problems with concentration, short-term memory, fatigue and chronic headaches.
One of those is former Army Spec. Michael Cain, who lost his right leg below the knee in a roadside explosion in Iraq in 2003. Today, he is still plagued with short-term memory loss, difficulty concentrating and irritability.
"If they tell me some important stuff, like appointments, if I don’t write it down or put it in my BlackBerry right away, I’m not going to remember," Cain says.
Unemployed and living on a medical retirement income, Cain says he is uncertain about his future.
"I really wish that they’d go away," he says of symptoms such as short-term memory loss and his tendency to startle easily. "I didn’t want them to tell me I had a brain problem, because I was a pretty smart person before. I had straight A’s. … It really frustrates me."
Pentagon officials estimated for the first time Wednesday that up to 360,000 Iraq and Afghanistan veterans may have suffered brain injuries. Among them are 45,000 to 90,000 veterans whose symptoms persist and warrant specialized care.
The detonation of any powerful explosive generates a blast wave of high pressure that spreads out at 1,600 feet per second from the point of explosion and travels hundreds of yards. The lethal blast wave is a two-part assault that rattles the brain against the skull. The initial shock wave of very high pressure is followed closely by the "secondary wind": a huge volume of displaced air flooding back into the area, again under high pressure. No helmet or armor can defend against such a massive wave front.
Blast waves cause severe concussions, resulting in loss of consciousness and obvious neurological deficits such as blindness, deafness and mental retardation. Blast waves causing TBIs can leave a 19-year-old private who could easily run a six-minute mile unable to stand or even to think.
"TBIs from Iraq are different," said P. Steven Macedo, a neurologist and former doctor at the Veterans Administration. Concussions from motorcycle accidents injure the brain by stretching or tearing it, he noted. But in Iraq, something else is going on. "When the sound wave moves through the brain, it seems to cause little gas bubbles to form," he said. "When they pop, it leaves a cavity. So you are littering people’s brains with these little holes."
Most of the families of our wounded that I have interviewed months, if not years, after the injury say the same thing: "Someone should have told us that with these closed-head injuries, things would not really get all that much better."
Scientists trying to understand traumatic brain injury from bomb blasts are finding the wound more insidious than they once thought.
They find that even when there are no outward signs of injury from the blast, cells deep within the brain can be altered, their metabolism changed, causing them to die, says Geoff Ling, an advance-research scientist with the Pentagon.
Military and civilian scientists worry whether a generation of servicemembers could emerge from the Iraq and Afghanistan wars with some form of brain damage which steadily becomes more severe.
The microscopic damage changes brain cell metabolism, Ibolja Cernak (a brain-injury scientist at Johns Hopkins University Applied Physics Laboratory) says, creating a cascading effect that leads to the premature aging and death of neurons that cannot be replaced.
A new report provides evidence linking traumatic brain injury sustained by troops in combat in Iraq and Afghanistan to a variety of long-term health problems including dementia, aggression, depression and symptoms similar to those seen in Parkinson’s disease.
There was "sufficient" evidence of an association between TBI and decline in neurocognitive function, long-term unemployment and problems with social relationships; Alzheimer’s-like dementia, endocrine dysfunction, depression, aggressive behavior, memory problems and early death.
Improvised bombs rattled former Army Spc. Adam Pittman a dozen times in his three tours in Iraq, most severely when his Bradley fighting vehicle ran over one hidden in the dirt in 2005.
Now, part of Pittman’s brain has gone dormant, and on most days he can’t think straight.
He leaves the room and forgets what he was searching for. He gets migraines so piercing that his right eye sometimes curls away from his left. Anger comes easily, inspiring rages that sometimes have his wife terrified for herself and their 3-year-old daughter.
And so it goes, after seven years of senseless war in Iraq, and nine years of senseless war in Afghanistan.