WASHINGTON, D.C.--After conducting his own investigation into medical care at one of America's largest Army bases, Rep. Harry Teague promised to dramatically expand an inquiry into the treatment of soldiers who have suffered mild traumatic brain injuries in Iraq and Afghanistan.

In a letter to medical commanders at Fort Bliss, the third-largest Army base in the country, Teague, D-N.M., wrote that he had turned up troubling evidence of systemic problems across the military in the treatment of soldiers suffering lingering cognitive difficulties as a result of roadside blasts.

Teague launched his inquiry after an investigation in June by NPR and ProPublica found that the military's medical system had failed to diagnose and treat tens of thousands of soldiers that had suffered mild traumatic brain injuries, often called one of the wars' signature injuries. The reports also found that soldiers had to fight for treatment at the military hospital at Fort Bliss, a base in El Paso, Texas that sprawls into Teague's district.

Teague said he planned to ask the Government Accountability Office, Congress' investigative arm, to conduct a "comprehensive examination" of the care provided to soldiers with traumatic brain injuries in the Defense Department and Veterans Affairs' medical systems.

"I am concerned that Fort Bliss, and by extension the military, is not adequately identifying, assessing, and treating patients with mild to moderate TBI case," Teague wrote.

A spokeswoman for the Pentagon said today that they were reviewing the letter. A Fort Bliss hospital spokesman said base commanders have not yet had time to respond to Teague's concerns.

The hospital's former commander had promised a "thorough review" of the care and treatment of soldiers after the NPR and ProPublica stories. A Fort Bliss spokesman said Friday he does not know if the review has been conducted.

Official military figures show that about 115,000 troops have suffered mild traumatic brain injuries since 2002. But based on interviews and unpublished military studies, we found evidence suggesting that tens of thousands go undiagnosed or sustain injuries that are never documented. Mild traumatic brain injuries, also known as concussions, are often referred to as invisible wounds because they are difficult to detect and leave no visible scars.

While most soldiers with concussions recover, civilian studies indicate that between 5 percent and 15 percent of people who suffer mild traumatic brain injuries have lingering cognitive problems. Unpublished studies of soldiers echo those findings. Such soldiers have trouble remembering, following directions or doing more than one task at a time.

Teague said that he had several concerns about the state of care at Fort Bliss. He said his investigators found that the Fort Bliss program had not been accredited by the Commission on the Accreditation of Rehabilitation Facilities, a leading trade organization.

He also said he was concerned that Fort Bliss did not have enough staff to treat the more than 1,100 soldiers who were diagnosed on base last year as suffering continuing problems from mild traumatic brain injuries. All in all, Teague wrote, soldiers with mild traumatic brain injuries were not receiving a high level of medical care.

He said that Fort Bliss and the military medical system needed to develop a comprehensive system of rehabilitation to help soldiers with continuing problems as a result of sustaining concussions.

"Our response to the epidemic of TBI among our service members and veterans should be overwhelming and unambiguous," he wrote. "The U.S. government should marshal every resource to treat and heal the invisible wounds of our current wars in Iraq and Afghanistan."

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