Some people are more prone to see floaters, such as those who are nearsighted or myopic, or need glasses to see distant objects clearly.

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Most people see floaters in their field of vision from time to time. Usually, they fade away and pose no risk. However, sometimes floaters—especially if accompanied by flashes—can indicate detachment or tearing of the retina, the light-sensitive sheet of cells on the back of the eye. A sudden increase in floaters or floaters accompanied by flashes of light require a doctor’s evaluation.

What Do Floaters Look Like?

People describe floaters as spots, specks, cobwebs, strands, wavy lines, strands, and other indistinct shapes that appear in their field of view. They’re especially noticeable if you’re looking against a plain or bright background, like a white wall or the blue sky. Floaters seem to appear and disappear without warning. If you try to look at them by moving your eyes, the floaters move along with your eyeball and may seem to dart away.

What Are Floaters?

Floaters are located in the gel-like vitreous humor inside the eyeball. With aging, the vitreous shrinks and gets thicker. This causes it to develop stranding or clumping, which casts shadows on the retina. These shadows are what you perceive as shapes floating in your field of view.

Some people are more prone to seeing floaters, such as those who are nearsighted or myopic (myopia requires corrective lenses to see distant objects clearly). You may see floaters after cataract surgery; inflammation (swelling) in the eye or being poked or struck in the eye may also trigger floaters.

Sometimes an increased number of floaters can be visible if the vitreous pulls away from the back of the eye—a vitreous detachment. Fibers in the vitreous are normally attached to the surface of the retina. With vitreous shrinkage, the fibers pull on the retina and break. This allows the vitreous to pull away from the retina, which may trigger a sudden increase in floaters. You may also see flashes of light in your peripheral vision.

When Should I See a Doctor?

Most of the time, floaters come and go and do not interfere with daily living. However, if they become so numerous or close together that they seriously interfere with vision, a doctor may consider removing some of the vitreous fluid with the floaters in it. This procedure is called a vitrectomy, but it is rarely performed for floaters.

Vitreous detachment itself is usually not dangerous, but sometimes it can cause a retinal tear or hole. In this case, the floaters and flashes may be accompanied by shadows in your peripheral vision or blurred vision. It may seem like a gray curtain is pulled across your vision. These signs of retinal detachment or tearing require immediate medical attention or can lead to blindness. So if you experience a sudden increase in floaters and flashes, get an eye exam promptly.