In glaucoma 20% optic nerve damage and minimal peripheral vision loss. eye drop reduced pressure from 31 to 16. what is my prognosis?

Favorable: You have early loss with probably no functional damage at this point. Glaucoma is successfully treated with regular follow-ups and diligent use of the treatment recommended. You can do well with reasonable effort on your part. And the advice of a good glaucoma ophthalmologist.

GOOD: That response to medication is grand. Keep up meds and keep contact periodically with the ophthalmologist. You're on the right path.