One concern that many of the patients at Georgia Eye Physicians and Surgeons bring to our attention has to do with little “cobwebs” or specks that seem to float about in their field of vision. These small, dark, shadowy shapes can look like spots, thread-like strands, or squiggly lines and just seem to lazily drift through the field of vision, moving as the eyes move and darting away when you try to look at them directly. These little visual irregularities are called floaters, and they are a relatively common, and usually harmless, by-product of the eyes’ internal anatomy.
The eye itself is actually a mostly-hollow sphere, filled with a clear, gel-like substance called the vitreous that helps the eye maintain its round shape. Throughout our youth, the vitreous has a consistency not unlike that of Jell-O, but as we age it begins to dissolve and liquefy in the center. Floaters are the result of tiny pieces of the vitreous gel breaking loose within the inner back portion of the eye and floating freely in the liquid, like bits of ice floating in water. While the eye cannot actually see the tiny bits themselves, the shadows that they cast on the retina as light passes through the eye create vaguely translucent images. This is why they are much more noticeable when you are looking at a bright, clear sky or a white computer screen. Floaters are, literally, floating free inside the eye, and so they move as the eye moves, creating the impression that they are “drifting” and never staying still when you try to focus on them.
Floaters are normally a relatively harmless condition. They generally do not impair vision and are likely to disappear over time. However, in some cases, they may be an indicator of a more serious eye problem called a retinal detachment. If the vitreous in the center of the eye becomes so liquefied that it can no longer maintain its shape, the heavier, more peripheral vitreous gel can collapse inward, pulling away from the retina or dislodging the retina itself from the inner back portion of the eye. This manual tugging or tearing of the retina stimulates the light sensitive photoreceptor cells, creating electrical impulses that are sent up the optic nerve and interpreted by the brain as bursts or streaks of light called flashes, or photopsia. This phenomenon can also occur when a sufficiently powerful blow to the head causes the retina to shift, causing the victim to temporarily “see stars.” If you notice a sudden appearance of a shower of floaters, particularly if it is accompanied by flashes, you should seek medical attention immediately. When addressed promptly, a detached or torn retina can be corrected with laser surgery or a freezing treatment that re-adheres the retina to the eye wall.
If you are concerned about the state of your vision, or are interested in any of the services we provide, please contact Georgia Eye Physicians and Surgeons to schedule an eye exam with Dr. William Segal or Dr. Marc Lay. Be sure to follow us on Facebook, Twitter, and Google+ for more tips for healthy eyes.