WASHINGTON D.C. - High-ranking VA officials faced questions from Congress Wednesday about why nearly 25,000 veterans nationwide were seen by doctors who weren’t qualified to diagnose traumatic brain injuries.

Rep. Tim Walz (D-MN) asked about the case of a Minnesota veteran featured in an ongoing KARE 11 News investigation.

Former Army Staff Sergeant and Green Beret Nate Anderson was repeatedly denied TBI benefits after being misdiagnosed by doctors who – by the VA’s own policy – were not qualified to make a TBI diagnosis.

“So my question is: What were they missing?” Walz asked during the Congressional hearing.

“We had a quality review process that perhaps one could say was a little light,” said David McLenachen, Deputy Undersecretary for Disability Assistance at the Veterans Benefits Administration.

Anderson was behind the wheel of a Humvee when it drove over a landmine in Afghanistan in 2008. He had to wait seven years before being properly diagnosed with a TBI by a qualified specialist.

“It’s ridiculous,” Anderson told KARE 11.

After a KARE 11 investigation last year revealed that unqualified doctors had been performing TBI exams at the Minneapolis VA, Congressman Walz demanded a national investigation.

Last month the VA disclosed there are nearly 25,000 veterans from all 50 states who had improper exams.

McLenachen acknowledged that when the VA reviewed TBI benefit decisions in the past, it did not always check whether the doctors doing the exams were specialists.

“Without a doubt improvement is needed in that area,” he testified during a House Veterans’ Affairs subcommittee hearing.

Now, he says the VA is checking qualifications every time. “A 100 percent quality check,” he told the committee.

Earlier this month, the VA began sending a letters to the veterans affected, saying they’re entitled to new exams and the possibility of retroactive benefits.

Some committee members questioned whether a single notification letter was enough.

”I’m concerned that it’s inadequate, said Rep. Dina Titus (D-NV).

If early results from TBI re-evaluations being done by specialists in Minnesota are an indication, the new exams elsewhere across the country could help thousands of veterans.

At Wednesday’s hearing VA officials disclosed that nearly half of the Minnesota veterans who, like Nate Anderson, were originally denied TBI benefits have now been told after re-examination they did suffer a traumatic brain injury.

“That’s a pretty high number,” McLenachen said. “We had to attribute that to the fact that it was done by the specialist rather than by a generalist.”

The physician who chairs the sub-committee credited the VA for taking action to correct the problem, but added he still has questions about how it happened. “Before we hold hands on the beach and sing Kumbaya we need some accountability here,” said Chairman Ralph Abraham (R-LA).

Congressman Walz took time to praise KARE 11 for exposing the problem.

“There was a tenacious young journalist named A.J. Lagoe that did some really fantastic journalism some really fair reporting and work at the Minneapolis VA,” Walz told the committee.