Kim, my daughter has anoxic brain injury and I did look into HBO for her. Also, my friend looked into it for her son. We read quite a bit about it and found that it does seem to cause improvement in most cases. It does help the most when the injury is recent. It is considered experimental, so insurance may not cover these expensive treatments. They must also be done daily for several months. Have your son evaluated by the rehab doctor or team to see if they recommend it for him. My daughter was evaluated and because of the length of time since the injury, it was not recommended. They felt there would be not significant improvement in her condition if she had the treatments.