PALO ALTO, CA (NBC) -- Soldiers coming back from the war in Iraq are being treated for many combat-related injuries, but doctors at the Veterans Administration Hospital in California have found something they haven't seen before.

Soldiers, with no obvious signs of trauma are going blind.

It's hard for Army Specialist Jason Kvasnak to remember every single explosion he survived in Iraq.

"We were in several IED blasts throughout the tour," Kvasnak said.

But Kvasnak remember the one that left him with the injuries no one saw coming.

"It was just massive concussive force and it thrust you forward, or whatever. I just felt really dazed afterwards and ringing in the ears and I couldn't really see straight," Kvasnak said.

Kvasnak hasn't been able to see straight since that blast.

He sees double, has sensitivity to light and the headaches he gets from trying to read or watch TV are so bad that he sometimes passes out.