Photopsia is a condition in which people see what appear to be flashes of light. Often times, a migraine will accompany this eye condition. Many people who suffer from frequent migraines use these flashes as indicators for an oncoming migraine. Several things may cause a person to see random flashing lights but the most common cause is shrinking vitreous in the eye. People over the age of 65 are more likely than younger people to experience photopsia.
The vitreous is the transparent substance that comprises the center of eyes. It is made mostly of water, accounts for roughly 75 percent of the volume of the eye, and gives the eye its shape and form. Shrinking of the vitreous in the eye most commonly leads to photopsia. This shrinking puts strain on attachment nodes, irritating the retina and causing it to send out electrical impulses that the brain interprets as flashes of light.
Other events aside from vitreous shrinkage can lead to this condition. Blunt force trauma to a person's head can easily cause the retina to pull away momentarily from the eyeball. When the retina pulls away from its position in the eye, a person may see momentary flashes of light. Posterior vitreous detachment and infarctions in the brain's occipital lobe may also lead to experiencing photopsia.
Photopsia is quite often a precursor to a migraine. Migraines can be caused when blood vessels in the brain spasm or when the retina detaches from connecting nerves. The flashes of light that accompany certain migraines may resemble sparks, lines of light, zig zags, or geometric patterns dancing through the air. Flashing lights can last for a brief moment or for quite a while throughout the duration of the migraine.
Perceiving frequent and sudden flashing lights without warning is an occurrence that should not be taken lightly. A person who regularly experiences flashing lights should consult his or her eye doctor as soon as possible. While experiencing mild light flashes is generally no cause for concern, in rare cases, this condition can lead to experiencing some level of vision loss.
In general, the vitreus of the eye shrinks as a person ages, becomes thinner in consistency, and begins pulling away from the retina. Roughly two-thirds of the population over 65 years old experience some level of vitreous shrinkage. While experiencing flashing lights may not be an uncommon occurrence for these people, a considerable increase in photopsia experiences may indicate that the retina is torn.