Have had symptom of imbalance for a year! been to ent, neurologist had mri's! no diagnosis! can you just have vertigo for no reason?

Perhaps these?: You may have "paroxysmal vertigo", a migraine epiphonomenon, or you might have inner ear issues, such a meniere's, or perhaps, an endolymphatic fistula. Hopefully, anemias, thyroid problems, decreased blood vessel flow, and medication adverse effects have been eliminated. Never hurts to get an additional opinion at nearby medical school.

Difficult: Dizziness, lightheadedness and vertigo can be quite a challenge to work up, diagnose and treat. First, it is oftentimes difficult to sort out if its imbalance versus vertigo versus lightheadedness. If its vertigo, there are a couple of tests that are very helpful. First is an electronystagmogram. Another is posturography and an audiogram. If negative, it could be a heart or blood pressure.