Hello and thanks for your question.
Do you have these episodes of vision "white-outs" before or during having a migraine? If not, do you have any visual phenomena associated with your migraines?
Does this happen in one eye only when it happens or does it happen to both eyes at the same time?
Do you notice any flashing or shimmering lights, nausea, light sensitivity or sensitivity to loud noises associated with these episodes?
Have you ever had any weakness, numbness, difficulty walking, talking or had any double vision with this?
Do you have any known eye problems such as diabetic retinopathy, glaucoma, or cataracts?