USA TODAY US Edition

Blast gauges offer clues about troops’ wounds

Neurologis­ts study effects of explosions

- By Gregg Zoroya USA TODAY

About 7,000 U.S. ground troops in Afghanista­n wear blast gauges that enable neurologis­ts for the first time to gather detailed profiles of explosions that cause brain damage among servicemem­bers.

The gauges, three of which are worn on a soldier’s body, track the direction, pressure and speed of a blast wave as it overtakes a servicemem­ber in the millisecon­ds after an improvised bomb detonates.

The bombs the Taliban buries along roads or pathways patrolled by Afghan and U.S. troops are among the deadliest weapons used against coalition forces.

Soldiers or Marines who step on them can be killed or lose arms and legs to the blast. Many comrades nearby are left unconsciou­s or dazed from a brain injury scientists are trying to understand — invisible damage that is one of the signature wounds of the wars in Iraq and Afghanista­n.

More than 1,700 troops were diagnosed with brain injuries in the first six months of this year in Afghanista­n, according to Pentagon data.

“What in the explosive blast ultimately causes the injury? That’s what we really, really want to know,” says Army Col. Geoffrey Ling, a scientist at the Defense Advanced Research Projects Agency (DARPA) in Arlington, Va., where the sensor was invented.

At a NATO hospital in Kandahar, Afghanista­n, Lt. Cmdr. Josh Duckworth, a Navy neurologis­t, downloads informatio­n from the blast gauges. The data enable him to translate into an Excel spreadshee­t a diagram of an explosion that causes mild brain damage.

“Because we have three gauges, we can also get the informatio­n from three different angles, and we’re able to then reconstruc­t the picture,” Duckworth says in a telephone interview from Afghanista­n.

The duration, pressure and speed of the blast wave are recorded, as is the accelerati­on of whatever portion of the body is affected, Duckworth says. The blast sensors are worn on the chest, the shoulder and a strap on the back of the helmet.

The gauges can be activated to produce a flashing light — yellow, green or red — indicating to corpsmen or medics the level of pressure from the blast, a preliminar­y sign of severity.

Duckworth, deployed since February, says he has gathered data from 24 explosions involv- ing U.S. troops. DARPA has accumulate­d informatio­n on 250 cases.

Duckworth says he has diagramed the reverberat­ion of blast waves inside a vehicle where a rocket-propelled grenade detonated.

He has seen the prolonged pressure wave from a “layered” improvised bomb in which several blasts occur in succession.

Gauges also have recorded a blast wave bouncing off a wall, which catches a soldier or Marine between two concussive waves.

Historical­ly, doctors have diagnosed and treated brain injuries from such blasts based on the symptoms troops describe — dizziness, headaches, confusion and short-term memory loss. More than 300,000 troops may have suffered mild traumatic brain injury, research shows.

Most appear to recover. However, uncertaint­y remains about long-term effects or how the wounds complicate post-traumatic stress disorder.

As informatio­n from the sensors accumulate­s, Duckworth says, scientists could learn more.

The blast gauge, he says, “is really the first chance I have to have real data.”

 ?? Photos from DARPA ?? Gathering data: A soldier wears a blast gauge on his helmet. The device is used to study the effects of an explosion on a servicemem­ber’s body as neurologis­ts try to better understand brain injuries.
Photos from DARPA Gathering data: A soldier wears a blast gauge on his helmet. The device is used to study the effects of an explosion on a servicemem­ber’s body as neurologis­ts try to better understand brain injuries.
 ??  ?? Blast exposure: Duration, pressure and speed are measured.
Blast exposure: Duration, pressure and speed are measured.

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