My first DBS surgery was 3 years ago, not very successful, so i didn't to proceed with the other side, until 3 months ago after seeing a different neurologist who referred me to a different neurosurgeon who performed the surgery on the other side. I see improvement of my dexterity and speech and rigidity after this one, so it's very important to choose your surgeon carefully. In both instances, they only shaved the parts where they have to work on.