Patients with successfully repaired retinal tears and detachments may have flashes for many months. I thought that only retinal breaks cause light flashes. Actually the most common cause of light flashes is the vitreous humor pulling away from the retina.
Light flashes occur in all three conditions.
Migraine can cause a jagged and flickering area of blocked vision with bright borders. It typically starts near the center of the vision and progresses to the peripheral vision before disappearing after about 30 minutes. Although patients describe this as occurring in one eye, in fact it occurs in the corresponding sides of the visual field in both eyes, as can be determined by covering one eye followed by the other when these are occurring. Migraines are thought to be caused by blood flow disturbances to the visual part of the brain. Blood flow problems can also occur with cervical spine problems, inflammation of the optic nerve, and hardening of the arteries, as well as very low blood pressure.