Causes of Flashing Lights

Migraine sufferers are well acquainted with the sensation that lights are flashing or flickering off in the corners of their field of vision. This sensation, called an aura, often precedes a migraine headache. But there are many other possible causes for flashing light symptoms, including everything from normal aging to a medical emergency. Your symptoms will guide your doctor.

Normal Aging

• As we grow older, we are more likely to notice flashes. This happens when the vitreous gel inside your eye pulls on or rubs the retina. If you have ever been hit in the eye and saw "stars,'' this is what you experienced. Floaters, which look like little black floating dots in the field of vision, are also common in the aging eye.

See Your Doctor

• If flashes seem intense or have appeared suddenly, or if they are accompanied by a loss of side vision or what seems like a dark curtain in your visual field, see your ophthalmologist immediately. This could be a sign of a torn or otherwise damaged retina. Likewise, the vitreous gel that covers the center of the eye becomes more liquefied as we age, and can shift position on the eye. This can result in seeing more flashes and floaters and should be checked by a doctor.

Entopic Phenomenon

• The entopic phenomenon is a normal state that may lead some people to think there is a problem with their eyes because they have never experienced it before. The entopic phenomenon can be seen especially well when looking at a bright blue sky. Rapid pinpoint sparks of light can be seen darting about in the central vision. Some people may think these sparks are floaters, but they are actually white blood cells moving through the blood capillaries of the retina. The entopic phenomenon does not indicate disease.