(AP) -- Behind Dan DeRosa's smiling face lurks a dull headache that never goes away. He suffers from memory lapses and hears a shrill ringing in his ears akin to the lingering squeal of a heavy metal concert.
These are some of the unseen scars left by a roadside bomb in Iraq. But at the Air Force's only traumatic brain injury clinic, the 26-year-old soldier is learning new skills to deal with the aftermath of the blast.
"I wouldn't say my memory really is getting any better, but my ability to adapt to the fact that my memory's really not getting any better has gotten a lot better," said DeRosa, a sergeant assigned to Fort Richardson in Anchorage.
He is among 1,500 patients screened since the TBI Clinic opened at neighboring Elmendorf Air Force Base and one of 75 currently monitored on a regular basis.
The clinic was established in early 2007 at the Elmendorf hospital. Base medics and officials anticipated that some of the 3,500 paratroopers with the 4th Airborne Brigade Combat Team deployed to Iraq from Fort Richardson would return with the war's signature wound.
Soon after the clinic opened, Army traumatic brain injury specialists were temporarily assigned to help the Air Force with returning soldiers.
The facility has since evolved with more services and staff experts including a case manager and a speech-language pathologist. It's now among a growing number of treatment outlets within the departments of Defense and Veterans Affairs for military members with brain injuries and the post traumatic stress disorder that frequently accompany them.
The DOD's health affairs office is assessing the Elmendorf clinic and many others. The DOD estimates that up to 20 percent of the roughly 1.8 million U.S. troops who have served in Iraq and Afghanistan have returned with brain injuries.
The vast majority of them suffer concussions such as those seen at the Air Force clinic, which also treats military members and relatives with brain injuries resulting from car crashes, hiking accidents and slipping on ice.
Without the Elmendorf service, the only options for Alaska-based troops would be facilities outside the remote state or long-distance programs by civilian providers, said Maj. Peter Osterbauer, a neurologist who heads the TBI clinic.
"It's not just the one brigade that was going to come back," Osterbauer said. "There's going to be more in the future."
Little more than a year after the 4th Brigade returned from Iraq, in fact, 3,500 of its paratroopers shipped out last month for an Afghanistan assignment.
Clinic officials say screening has improved to more accurately diagnose cases like DeRosa's. But as with so many others hurt in Iraq and Afghanistan, his injury wasn't immediately apparent after the initial shock of the June 2007 explosion.
DeRosa was driving a Humvee with three passengers outside Baghdad when the bomb went off beneath the engine, flinging the vehicle 50 yards into a ditch. No one was killed, he said, but one soldier suffered ruptured eardrums, another's knee was damaged and the gunner flew through the turret "like a champagne cork." DeRosa stumbled out of the Humvee with a broken arm and shrapnel wounds along the edge of his body armor.
DeRosa didn't have time to dwell on his more long-term symptoms. He dismissed them as wartime stress. It wasn't until after returning six months later that his problems became apparent, particularly after a long visit with his family in his hometown of Berkley, Mass.
"I started noticing things," he said. "My hearing was not as good, I still had a headache, I wasn't sleeping well, I wasn't sure where I put my car keys."
Back in Alaska, a post-deployment screening showed DeRosa needed to be checked out further by a battery of tests. Ultimately diagnosed with TBI, he became a patient at the Elmendorf clinic last spring.
DeRosa's progress is monitored by Osterbauer. He meets three times a week with Maj. Ava Craig, an Air Force speech pathologist who said DeRosa has shown improvements in such areas as language, reader comprehension and concentration.
None of the medications prescribed for his headaches has worked, which makes DeRosa eligible for Botox injections, highly effective in treating headaches.
Botox has worked wonders for Staff Sgt. Gabriel Fierros, whose face and left eye were struck by shrapnel when his helicopter was shot down by small-arms fire outside Baghdad in April 2007.
The 28-year-old soldier from Marengo, Ill., spent seven months at Walter Reed Army Medical Center in Washington, recovering from a hard blow he compares to "a baseball bat to the face." He also hears a high-pitched ringing in his ears, has memory problems and struggles with irritability, nightmares and other symptoms of post-traumatic stress.
He receives Botox every three months. In the latest round, Osterbauer delivered 18 injections to the front of Fierros' head and another 10 to 15 in the back. Fierros took it stoically.
"When I first came here, I always had a headache. I was always worn out, tired. I couldn't focus, couldn't concentrate. I couldn't remember my cell phone number, couldn't remember how to get home," he said. "Seeing the different specialists has helped a lot."
Officials at Fort Wainwright in Fairbanks, 260 miles to the north, like the concept so much, they are planning to open up a similar TBI clinic near the post hospital within six months.
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