Shock to the System

Soldiers who manage to walk away from explosions in Iraq may actually be suffering terrible—yet invisible—brain trauma. Could blast waves be fueling a new breed of injury?

By Eric Hagerman Posted 08.22.2008 at 9:54 am 8 Comments

HARD-HIT : Army medic Frederick Hussey, who earned two purple hearts in Iraq, at home in Columbia, South Carolina John B. Carnett

Thousands of American soldiers are coming home with similar complaints. The big mystery is why. Plenty of them have been hit in the head like Hussey, but even those who haven’t are turning up with unusually protracted symptoms that resemble those of a serious brain injury. One tantalizing clue is that among the 2,500 soldiers who returned from yearlong tours in 2006, 62 percent reported that they had been exposed to two or more explosions, whereas only 2 percent had suffered gunshot wounds. The trend has researchers wondering: Is there some unaccounted-for mechanism in the blast itself that’s causing hidden brain injuries?

Neuroscientist Ibolja Cernak, a medical director at Johns Hopkins University’s Applied Physics Laboratory, is one of a handful of researchers across the country trying to find out. She believes that blasts may do more than just rattle the head; the shock waves also compress the torso, which may cause pressure waves to ripple through blood vessels like miniature tsunamis, rushing into the brain and damaging tissue. Army Colonel Geoffrey Ling, a neurologist who has treated troops in both Afghanistan and Iraq, agrees that there’s probably more to war-zone head trauma than the blunt forces at play in a car accident or football collision [see “Gridiron Gear Goes to War,” page 86]. His own theory pinpoints electromagnetic pulses as one possible culprit. Blasts emit intense magnetic fields that may damage brain cells, he contends. “People are seeing a syndrome among these returning veterans,” Ling says. “The question I have is, what’s causing it? If I know the answer to that, potentially I can prevent it.”

With 178,000 soldiers deployed in Iraq and Afghanistan, and thousands more gearing up for second, third and sometimes fourth tours of duty, these questions have sparked a surge in funding. Late last year, Congress earmarked $300 million for basic science research on brain injuries and PTSD. The National Institutes of Neurological Disorders and Stroke recently called together more than 100 doctors, neuroscientists, physicists and biomechanical engineers to review the little that is known about blast-related brain injuries. And the Defense Advanced Research Projects Agency, or Darpa, is in the midst of a yearlong, $9-million effort, led by Ling, to study the effects of blasts on the brain—from chemical and structural alterations to, ultimately, behavioral symptoms.

Meanwhile, soldiers and their doctors are waiting for answers to rudimentary questions about diagnosis and treatment. Above all, what everyone really wants to know is whether blast exposure—with or without direct damage to the head—triggers long-term neurological problems that are waiting to ambush an entire population of veterans.

A Hidden Danger

Some 97 percent of American troops wounded in Iraq come home alive. The survival rate is higher than in any other war, and is largely thanks to improvements in body armor, evacuation procedures and medical care. The Kevlar vests and helmets worn by today’s combat troops, for instance, have saved soldiers who may have otherwise died from bullets and shrapnel. The catch is that more of those soldiers are coming home with permanent injuries from explosions than ever before.

There are many ways to be wounded in a blast. The detonation turns the bomb material into pressurized gases that expand instantly, radiating a supersonic wall of air many times as powerful as hurricane-force winds. That primary blast wave leaves a vacuum in its wake, and the pressure differential creates shearing forces that cause organs to expand and then collapse, crushing lungs and bursting eardrums. Shrapnel and debris can cause further damage, and there is always the chance of getting burned by the heat or slammed into something.

Previous Article: Is the Web the Newest Front Line?

Next Article: How Long Would it Take to Walk a Light-Year?

8 Comments

link to this comment

lpbman

08/24/08 at 12:02 pm

Are you sure that Rand survey was talking about all deployed troops? That number seems high, and I wonder if they weren't referring to front line soldiers.
Anyone have a direct reference?

link to this comment

JDiez

08/25/08 at 6:56 am

Perhaps would be good to try a Faraday cage kind of system integrated inside a helmet.
That's a way to protect from EMP

link to this comment

Bentfish

08/25/08 at 10:08 pm

The first commentor may have been dropped on his head as a child. I suffered a TBI in 1991 and spent the next fifteen years recovering from it. When I awoke from an induced coma, my IQ had been cut in half. I was Forrest Gump without the math. It took 15 years to get it back to 124, still a 20% loss of cognitive function. And will they even have that much to spare? I still suffer the sequeli today.
Is the army willing to put the monies needed for thousands to recover from this type of long term disability. Or are we headed to a situation like the post vietnam era. With untreated soliers living under bridges and self medicating with drugs and alcohol.

link to this comment

Wake2sa

09/06/08 at 5:30 pm

The brief but extreme blast forces on the thorax and abdomen force venous and arterial blood as well as cerebral spinal fluid retrograde into the cranium like multiple caliber shotgun blasts through foramina or openings at the base of the skull. The brain, having no place to go, receives multiple traumatic squeezing forces due to the different diameters of these openings. Neuroimaging should reveal evidence of injury in keeping with these anatomic alterations along the inferior surfaces of the brain and along the course of major vascular supply and CSF spaces. I propose preventing or reducing these blast forces by wearing a blast resistant, hard shell of strong carbon composite material over the entire chest and abdomen minimizing these pressures to the brain and thereby preventing these devastating injuries.

link to this comment

wafflehead

10/06/08 at 3:51 pm

i'm not sure, what is needed, but the one thing thats certain is that a much better system is needed to protect our troops!

link to this comment

bpursun

10/22/08 at 11:31 am

I FOUND THAT THIS ARTICLE IS CORRECT IN THE SYPTOMS, BUT WRONG IN THE REASON. THIS IS BATTLE FATIGUE, AND THE SAME AS THE VIETNAM VETERANS SUFFERED.
THE EARLY ARTICLE IN THE SAME ISSUE IS VERY ACCURATE.
LONG PERIONS OF STRESS = PLUS A MAJOR SHOCK OF ANY KIND IS THE ISSUE.
IT PRODUCES CORTISON WHICH DAMAGES THE HIPPOCAMPUR AND THE ENTIRE PITUATARY GLAND. THIS AFFECT THE ENTIRE BODAY. THE DIAGRAM AT THE END IS EXTREMELY CORRECT IN THE RUSULT. RESEACH IT YOURSELF AND FIND OUT.

link to this comment

Mike Cook

from Kent, WA

11/20/08 at 5:37 am

Way back in the 1950's and 1960's there was a German guy who had survived a grenade explosion next to his body in W.W.II and developed a theory about how a properly positioned human body can survive an explosion if the shrapnel doesn't kill the subject. The ex-soldier developed a carnival routine which I witnessed during a demolition derby half-time. He built a coffin out of cheap plywood and about a foot from the head of it was placed a stick of 50% dynamite. Then he would lay down in the coffin without even a helmet and detonate the explosive, spectacularly demolishing the coffin and leaving himself unharmed.

As an entertainment routine this act was spectacular (I believe I read about it in Popular Science before actually seeing it) but took place so quickly that the guy had to do a lot of talking and build-up in order to hold 15 minutes of the audience's attention until a climax that would only take a micro-second.

In his heavily accented English the guy admitted that he had gone deaf from doing this stunt. He also said that the closest he had come to being really hurt was when he performed the routine out on the end of a pier at a marina show in Florida. The plan was that the blast would drop him spectacularly into the water. It worked as planned but what he didn't know is that explosions create a great amount of static electricity. As soon as he contacted the water he suffered serious burns over a good part of his body.

I can't remember his name other than that it was German.

link to this comment

Neuuubeh

01/09/09 at 11:26 am

So, shockwaves from explosions can damage the human body... How is this a surprise really? Receiving an abrupt blow to the head can lead to coma, but apprarently having a grenade explode a couple of meters from the head cannot be dangerous??

This kind of reminds me of the first experiments with atomic weaponry, noone thought the radiation could be "bad" - we all know how that turned out.