Floaters & Flashes
What Are Floaters?
Floaters are often described by people as "specks," "threads," "bugs" or "spots" that they see moving about in their field of vision. Floaters are most visible when looking at a plain background, especially when reading or staring at a blank wall or blue sky.
In most cases, floaters are just a nuisance, but occasionally they can be an indication of a more serious problem, such as a retinal tear, diabetic eye disease or inflammation in the eye.
Floaters are usually just small clumps of gel that form in the vitreous (vi-tree-us), the clear, gelatin-like fluid that fills the space inside the eye behind the lens. The vitreous accounts for about two-thirds of the volume and weight of the eye, and is responsible for maintaining the shape of the eye. The vitreous is 99% water. The remaining 1% is a mixture of collagen and hyaluronic acid which gives it its jelly-like characteristic. The vitreous is important in maintaining the transparency needed for unobstructed passage of light rays from the lens to the retina where images are then transferred to the brain.
Floaters can be more noticeable when staring at the sky or a wall.
What Causes Floaters?
At birth, the vitreous has the consistency of gelatin and is perfectly transparent. With age, however, this gel shrinks and pulls away from the retina, forming fluid-filled cavities and collagen residues (clumps) which become noticeable in the field of vision as floaters.
These cavities and clumps cast shadows on the retina (the light sensitive inner layer of the eye) which are seen as “floating” across the field of vision. Floaters are visible both to the patient looking out and, interestingly, usually to the eye doctor looking in.
At least 65 percent of people over age 60 have floaters. Floaters, however, can occur at any age (especially in people who are nearsighted or have had cataract surgery) and tend to increase in number with time.
Are Floaters Serious?
In most cases, floaters are merely a harmless annoyance that may appear, disappear, remain stationary, dart around, or change in size. Occasionally, however, they are an indication of a serious concern. For example, as the vitreous gel pulls away, the retina may be torn. This sometimes causes minor bleeding in the eye, which can appear as a cluster of new floaters. The tear can become even more serious if it progresses to a retinal detachment—separation of the retina from the back wall of the eye. In other cases, floaters may be a sign of diabetic eye disease or inflammation in the eye.
You should schedule an immediate eye appointment if the onset of or increase in floaters is sudden, or appears as "cobwebs," "spiders," or an expanding “ink blot.”
What Can Be Done About Floaters?
Throughout the day, we typically move our eyes from side to side. If a floater is annoying you, try looking up and down and in different directions. This motion causes the vitreous gel to swirl in different currents and may be effective in moving the floater out of your direct line of vision. If your floaters are especially bothersome, however, you may be a candidate for vitreolysis.
Laser Treatment for Floaters
Until recently, the only effective way to treat floaters was with a “vitrectomy,” an invasive, cutting surgical procedure involving removal of all or part of the vitreous humor and replacement with an electrolyte saltwater solution. Vitrectomy is able to remove all types of floaters, however, because this procedure has a risk of bleeding, infection and cataract formation, most patients were typically told to forego surgery and “just live with it.” Now, however, there is a new option. Vitreolysis is a non-incisional outpatient laser procedure that may reduce specific types of floaters that are significantly distracting enough that they affect your comfort and ability to perform tasks.
Candidacy for Treatment
If it has been confirmed that your floaters are not a sign of something more serious, yet they are significantly distracting enough that they affect your comfort and ability to perform tasks, you may be eligible for vitreolysis.
The best candidates are patients who are over age 50 and have had cataract surgery. However, not all floaters are suited for laser treatment. Floaters that result from a posterior vitreous detachment (PVD) are readily treatable, whereas the large diffuse (spread out over a wide area) floaters common in young nearsighted patients are very difficult to treat. Your eye care specialist will conduct a comprehensive dilated eye examination to determine if vitreolysis is appropriate for you. If it is, the procedure is typically covered by insurance.
Flash of Light
What Are Flashes?
Glowing, streaks or flashes of light occurring in the field of vision are called flashes or “photopsias.” This flashing rarely lasts more than a fraction of a second and may recur at frequent intervals but then disappear for weeks. Flashes usually affect one eye, although a similar episode may occur in the other. Unlike floaters, flashes are usually noticed when moving the eye and in situations where there is dim lighting, no light at all, or the eyes are closed.
What Causes Flashes?
There is no flashing light actually present when you experience flashes. Instead, the flashing light is created when the vitreous gel happens to tug on the retina. This pulling causes internal stimulation of the retina that the brain perceives as flashing lights.
Know When to Seek Help
Floaters and flashes are not usually a cause for alarm—there is only a 1 in 1,000 chance that they are a sign of a retinal detachment. However, it is important to be aware of what is normal for your eyes, so that you can determine if there is an increase in total and/or severity of occurrences that warrants attention. This may be a sign of a serious condition, such as diabetic retinopathy, vascular abnormalities (retinal hemorrhages, carotid artery disease, etc.), or the beginning of a retinal detachment.
If you notice new and different floaters or flashes of light (different than before) or a persistent curtain over your vision; you must call your eye care specialist within two days to be checked!
For more information or a comprehensive examination . . .
Since 1985, Eye Care Specialists has provided comprehensive medical, surgical and laser care for virtually every eye condition to more than 185,000 people. If you would like our free educational booklet on the eye concern reviewed above, please complete this form or call our Communications & Education Department at 414-321-7035. To schedule a comprehensive eye examination or a second opinion evaluation, call any of our three convenient Milwaukee-area locations directly.