Photopsia is the term that is used for the condition when people appear to see flashes of light. Frequently, these flashes appear alongside a migraine, and in fact, migraine sufferers use the flashes as a signal of an upcoming migraine.
Those people over the age of 65 are the most likely to be affected, and the most common cause of these eye flashes is the shrinkage of the vitreous humor within the eye.
The vitreous humor is the transparent substance in the centre of the eyes, mostly made up of water, and is responsible for the shape and form of the eye.
Usually, photopsia is caused by the shrinking of the vitreous humor, which applies tension to the attachment points, which agitates the retina causing the emission of electrical impulses that are interpreted as flashes of light by the brain.
Vitreous humor shrinkage is not the only cause of photopsia. For example, severe impact to the head can easily cause the retina to pull away from the eyeball, and when this happens momentary flashes of light may be seen.
As mentioned, photopsia can be the signal for the onset of a migraine. Migraines may be caused when the blood vessels in the brain quiver, or if the retina becomes detached from connecting nerves.
The flashing lights, which may look like sparks, zig zags or lines of light, may last for a brief period or be longer lasting throughout the course of the migraine.
This perception of flashes of light should be treated seriously, and prompt investigation by a medical professional is advisable.
Generally speaking, the experience of eye flashes is no reason for concern, but in very rare instances, photopsia can lead to certain levels of loss of vision.
During the normal ageing process, the vitreous humor will shrink, becomes thinner, and will begin to pull away from the retina.
In fact, approximately two thirds of the over 65s will be affected by some degree of vitreous humor shrinkage, leading to many experiencing flashing lights.
It should be kept in mind that a major increase in the number of photopsia occurrences can possibly indicate a torn retina.
Clearly, it is essential to recognize and understand photopsia signs.