The symptoms of retinal migraine may include:

• partial or total loss of vision in one eye - this usually lasts 10 to 20 minutes before vision gradually returns
• headache - this may happen before, during or after the vision attack

It's unusual for an episode of vision loss to last longer than an hour. The same eye is affected every time in almost all cases.
Vision may slowly become blurred or dimmed, or there may be flashes of light. Some people see a mosaic-like...