I had ON but did not take any steroids. It took about 6 months for my vision to return to normal.

I have been told by my Neurologist that if a new symptom lasts longer than 24 hours then it's considered an exacerbation.

I have had what is considered an "exacerbation" but I don't contact my Neuro whenever it happens. All he can do is offer symptom meds (steroids) and I usually just tolerate whatever it is (dizziness, vision, balance, etc.).

Some Neuros like to treat more aggressively than others. Mine knows that I don't like taking anything except in severe cases. Once you find a Neuro that you like they'll get to know what you can tolerate for symptom relief.