What is the success rate of vision therapy? is it a reputable field? does it work well in reducing headaches as well?

no data: Vision therapy is practiced by optometrists who charge a great deal for the sessions. There are no reputable clinical studies; only anecdotal accounts. Most practitioners of this are charismatic and committed, but their results are unsubstantiated and probably not worth the effort or the money. See an ophthalmologist first before entering into such a program.