(WRC) -- William Cook was just 18 years old, when he stepped on IED while he was deployed in Iraq.
Cook, now 22, lost part of his left leg, damaged nerves and tendons in his right leg and lost tissue in one arm.
Doctors patched him up and gave him a prosthetic.
But he still didn't feel quite right.
Doctors told Cook to see a therapist and prescribed him a slew of medications, but nothing helped until a friend referred him to Dr. Stephen Xenakis, a retired Army brigadier general and a psychiatrist, who believed all those symptoms were consistent with a traumatic brain injury.
Xenakis recommended a new treatment using a hyperbaric oxygen tank.
Patients lie in the tank for an hour, where they're submerged in 100 percent oxygen that's under increased pressure.
It's similar to going 17 feet under water.
Patient do 40 sessions total, but Xenakis says after about 20 sessions, patients usually start to feel better, their mood starts improving and they feel more alert and focused and headaches go away.
William Cook has had close to 40 treatments now.
He says he's finally feeling like himself again, which is giving him new hope for his future.
He even plans to start college this spring.
Right now doctors are testing the efficacy of this treatment and they say so far 100 percent of the people who have used it feel better.
But it's not cheap.
It costs $250 dollars a session and insurance does not cover it.
However, they are working with veterans for free.