I had horrible balance before getting CK (CyberKnife) treatment: Vertigo attacks and oscillopsia (check it out on Wikipedia, if you don't know what oscillopsia is) for years, along with general disequilibrium and "wonky-head" on relatively good days. Since getting CK, my balance has recovered around 97%, subjectively, and I am able to do virtually all the outdoor sport activities I could before. My doctor, Steven Chang, thought my improvement was due to my tumor eventually shrinking after my treatments (after first swelling in reaction to the radiation), thereby putting less pressure on my balance nerve. Just be aware that not everyone who gets CK has an improvement in balance. YMMV.
Good luck, and best wishes,