hi
hi im not a doctor but here's a possiblity, with a stroke you somthimes will get a numbness to the arm,or head. with a magraine, the visual distortion you get is when the part of the brain this is affected will swell, just like a head ache, whicah can be due too dehydration. the eye ball itself will expercience a small level of stress and you might get a temporary asigmatism, its just like when you rub your eye and you get little speckles of light, that is why it images look incomplete. after the magirate disapears so does the stress on the eye and the visual distortion disapears, and you ca be left with a headache. you can experience the full migrane or a visual aura, google it as well.