The small specks or “bugs” that many people see moving in their field of vision are called floaters. They are frequently visible when looking at a plain background such as a blank wall or blue sky. Floaters were described long ago, in Roman times, as flying flies (“muscae volitantes”).
Floaters are small clumps of cells or tissue that form in the VITREOUS gel, the clear jelly-like substance that fills the inside cavity of the eye. Although they appear to be in front of the eye, they are actually floating in the vitreous gel and are seen as shadows cast on the RETINA (the light-sensing inner layer of the eye).
The appearance of floaters, whether in the form of little dots, circles, lines, or cobwebs, may cause much concern, especially if they develop suddenly; however, they are usually of little importance, representing a normal aging process for most people. As one ages, the vitreous gel tends to liquefy. Although small floaters can be seen at any age, the larger, more noticeable ones that some times appear suddenly tend to come when the vitre ous gel liquefies enough to pull away from the retina. This is caused a POSTERIOR VITREOUS DETACHMENT (PVD). Brief flashes of light are often noticed with the new floaters that appear after this PVD event.
Anything that stimulates the retina can cause light flashes. Light flash phenomena also can originate from the visual centers of the brain such as what sometimes occurs before a migraine headache. Light flashes often occur when the vitreous gel pulls on or separates from the retina such as during or shortly after a posterior vitreous detachment (PVD).
Usually not, but there are exceptions. During or after a posterior vitreous separation, the retina may be torn, sometimes causing bleeding in the eye which may appear as a group of new floaters or flashes. Tears in the retina are potentially serious because they can lead to retinal detachment and visual loss. Retinal tears typically need to be sealed to prevent retinal detachment.
Uncommonly, floaters result from inflammation within the eye or from crystal-like deposits which form in the vitreous gel.
Without examination by an ophthalmologist, there is no way for a person to determine whether floaters or flashes are serious. Any sudden onset of many new floaters or flashes of light should be evaluated promptly by your eye doctor.
Floaters may sometimes interfere with clear vision, often when reading, and can be quite annoying. If a floater appears directly in your line of vision, the best thing to do is move your eye around, which will cause the inside fluid to swirl and allow the floater to move out of the way. We are most accustomed to moving our eyes back and forth, but looking up and down will cause different currents within the eye and may be more effective in getting the floaters out of the way. Often, floaters will break up or shift to the side with time, making them less noticeable or bothersome. In rare cases where large floaters are debilitating and interfere significantly with a patient’s vision, a vitrectomy can be performed to surgically remove the vitreous gel and floaters.
If your doctor diagnoses you with a retinal tear, a laser procedure in the office can often be used to seal the edges and significantly reduce the risk of developing a retinal detachment, which is a potentially blinding condition. In some cases, a freezing treatment (cryopexy) can also be used.