Don't quote me on this, but in order to get your class 1 medical I believe you only need to be within the boundaries of -5/+5 dipoles. They discourage people from having laser eye surgery unless it's vital. I have no idea about the US medicals, however I can't imagine them being much different. If you still believe that you should go ahead, I suggest you do it ASAP as i'm sure there will be many limitations within the initial months.