that's not good. I don't see how a blow to the head would cause a swollen optic nerve. I can think of too many other causes. Hopefully, a brain MRI has eliminated any other causes. The swelling needs to go down quickly to reduce or eliminate the chances of vision loss. I would think her season is over as one would not want to take a chance on a repeat injury that could cause permanent vision loss. But that's for the doctors to determine as she recovers.