Can light flashes be caused by forces not related to the retina of the eye?
Yes. 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. Low blood pressure can cause people to see stars or specks of light, particularly if they change position quickly. An example would be standing quickly from a sitting position or rising quickly after stooping or bending over. Pregnancy related high blood pressure (pre-eclampsia) can also cause light flashes.
