What are floaters?Spots and floaters are particles of debris, cells, pigment, or tissue fiber that move and float around the eyes, usually when we move them. When light enters the eye and hits the particles, it casts a shadow on the retina, much like holding your hand in front of a movie projector. We see this shadow as something moving out or across our visual field. These visible particles exist within the fluid inside the eye. We notice the particles when they move into our line of vision. When the fibers clump together, they become more dense and solid, thus allowing us to see them easier. They sometimes appear with flashes of light.
Spots and floaters appear in various shapes and sizes, sometimes resembling threads or cobwebs. They move when our eyes move and dart away if we try to look directly at them. Although usually harmless, these visible particles are sometimes frightening and can be annoying. Fortunately, they seem to disappear as fast as they appear, usually without notice.
What causes spots and floaters?Our eyes are made of a clear, jelly-like fluid called the vitreous. When the eyes are formed, small pieces of protein or other matter may be left floating or suspended in the vitreous. If these particles are large enough or become clumped together, they become visible to us.
Spots and floaters may also be caused by aging. As we get older, the eye fluid begins to thicken and deteriorate, causing particles to become more visible. Also, certain eye diseases or injuries can sometimes produce spots in our vision. For example, vitreous or retinal detachment are conditions that may cause disturbances in our line of vision.
What are the symptoms of spots and floaters?Most people occasionally see spots and floaters. These spots are usually more visible in bright light and when looking at a blank wall. Some people notice them most while reading. Spots and floaters usually appear in one eye at a time and are, in most cases, painless.
How are spots and floaters treated?Spots and floaters are usually not serious, and will disappear as soon as they move out of our field of vision. However, spots and floaters can sometimes signal a serious eye condition and will need immediate attention. If you suddenly see an increase in the size and number of spots and floaters, a comprehensive eye examination will be needed to determine the cause.
In rare cases, the eye's vitreous can become detached, causing small tears in the retina. The damaged part of the retina can sometimes appear as a spot in our vision. If untreated, the retina may eventually become detached, resulting in loss of vision. An eye doctor will be able to determine the cause of spots and floaters by looking into the eye with a special instrument called an ophthalmoscope. If a detachment of the vitreous or retina is found, surgery may be needed to preserve your vision.
Source: American Optometric Association, Spots and Floaters. 18 Jul 2007.