Why do i get silvery squiggly lines that move from one side of vision to teh other after eating? is it related to high or low blood glucose?

Visual Migraine?: A visual migraine is the visual aura of a migraine headache, but without the headache. This can be triggered by certain foods. People will see in both eyes either zig zag flashing lights or an effect like heat coming off of a car for 5-30 minutes, and the visual disturbance moves peripherally to the side and then stops. There is usually a blind spot in the vision as well, where the lines are.