Vision changes may indicate a serious problem with the tissue that lines the back of the eyeball (retina), optic nerve, or blood vessels in the eye. Evaluation by a health professional is needed right away for sudden vision changes, such as:
Flashes of light (photopsia). Photopsia is brief but recurrent streaks, sparks, or flickers of light, particularly when you move your eyes or head. The flashes of light may be easier to see when you look toward a dark background. The brief flashes may occur with retinal detachment.