What are "floaters"?
You may sometimes see small specks or clouds moving in your field of vision; these are called floaters. You can often notice them more when looking at a plain background, like a blank wall or a blue sky (similar to the image shown). Floaters are actually tiny clumps of cells or material inside the vitreous (the clear, gel-like fluid that fills the inside of your eye). While these objects look like they are in front of your eye, they are actually floating inside of it. What you see are the shadows they cast on the retina, which is the layer of cells lining the back of the eye that senses light and allows you to see. Floaters can appear as different shapes, such as dots, circles, lines, clouds, or cobwebs. They can be distracting at first, but eventually tend to "settle" away from the retina, becoming less bothersome. They do not typically completely resolve, however there are other, more serious causes of floaters that may need attention right away. It's especially important to see your ophthalmologist if you notice new floaters.
What are "flashes"?
When the vitreous gel pulls on the retina, you may see flashes of light or lightning-like streaks. You may have experienced this same sensation if you have ever been hit in the eye and seen "stars". The flashes of light can appear off and on for several weeks or months. As we grow older, it is more common to experience floaters and flashes as the vitreous gel changes with age, gradually pulling away from the inside surface of the eye.
What causes flashes and floaters?
Floaters and flashes are also caused by posterior vitreous detachment (PVD), where the vitreous gel pulls away from the back of the eye. This condition is more common in people who:
Are nearsighted
Have undergone cataract operations
Have had YAG laser surgery of the eye
Have had inflammation (swelling) inside the eye
Have had an injury to the eye
The appearance of floaters and flashes may be alarming, especially if they develop suddenly. To find out if a retinal tear, hole, or detachment is occuring, you should call your ophthalmologist right away if you notice the following symptoms:
A sudden increase in size and number of floaters
A sudden appearance of flashes
Having a shadow or curtain appear in the periphery (side) of your vision
Seeing a gray curtain moving across your field of vision
Having a sudden decrease in vision
How are floaters treated?
For people who have floaters that are simply annoying, no treatment is recommended. On rare occasions, floaters can be so dense and numerous that they significantly affect vision. In these cases, a vitrectomy (a surgical procedure that removes floaters from the vitreous) may be offered. A vitrectomy removes the vitreous gel, along with its floating debris from the eye, and is then replaced with a saline solution. Because the vitreous is mostly water, you will not notice any change between the salt solution and the original vitreous. This operation carries significant risks to sight because of possible complications, which include retinal detachment, retinal tears, and cataracts. Most eye surgeons are reluctant to recommend this surgery unless the floaters seriously interfere with vision.
Posterior Vitreous Detachment (PVD)
As we age, the vitreous slowly shrinks and pulls on the retinal surface. Usually the fibers intertwined within the vitreous break, allowing the vitreous to separate and shrink away from the retina. This is called a vitreous detachment. A vitreous detachment is a common condition that usually affects people over age 50, and is very common after age 80. People who are nearsighted are also at an increased risk. Although a vitreous detachment does not necessarily threaten sight, once in a while some of the vitreous fibers pull so hard on the retina that they create a retinal tear or detachment. Both of these conditions are sight-threatening and must be treated immediately. If left untreated, a detached retina can lead to permanent vision loss in the affected eye. Those who experience a sudden increase in floaters or flashes, or decreased peripheral or central visino should have an ophthalmologist examine their eyes as soon as possible.