Floaters
Also called: Muscae volitantes · Eye floaters · Vitreous floaters · Myodesopsia · Myiodesopsia
Small grey threads, dots, or cobwebs that drift across your vision and dart away when you look at them. They are shadows of tiny clumps inside the eye. They are common and usually harmless.
How common
Does this happen to you?
How it works
The eye is filled with a clear jelly called the vitreous. It is mostly water held in a mesh of collagen fibres2. Over time, some fibres clump together2. A clump casts a shadow on the retina, and you see the shadow as a thread, dot, or cobweb1. Floaters follow the quick movements of the eye but drift slowly inside the jelly. So they stay to one side and slide away when you try to look at them1. They show best against a bright, plain background such as a blue sky or a blank wall1.
The Latin name, muscae volitantes, means “flying flies”1. With age, the jelly liquefies and shrinks6. In older adults it can pull away from the retina, a change called posterior vitreous detachment. This can bring a sudden burst of new floaters3.
Floaters usually become less bothersome over time, as people learn to ignore them1. Symptoms may ease within about 3 months. For some people they do not6.
How common it is
The main figure comes from one survey. 603 adults answered it through a free Android app, and 76% said they had noticed floaters5. The people chose to take part, and most were young. Fewer than 5% were over 505. Age, sex, and race made no clear difference in that survey5. About a third of those with floaters rated them at least moderately bothersome. Short-sighted people were about 3.5 times as likely to say so as people with normal sight. Long-sighted people were about 4.4 times as likely5. Older groups may differ. The jelly typically pulls away from the retina after age 506.
Is it a problem?
Usually no. Floaters are usually benign6. They do not cause serious problems for most people1. Surgery exists for severe cases, but it carries its own risks, including retinal detachment1.
Get checked the same day if you notice:
- a sudden shower of many new floaters,
- flashes of light,
- a dark curtain or shadow across part of your view.
These can mean the retina is tearing or pulling away4. Quick treatment gives the best results. Left alone, it can cause permanent loss of vision4. Also get checked if new floaters appear after a blow to the eye6.
Sources and further material
- Wikipedia Floater
- Wikipedia Retinal detachment The emergency that a sudden shower of floaters with flashes can signal.
- NCBI Prevalence of vitreous floaters in a community sample of smartphone users Survey of 603 app users. 76% saw floaters. Found no effect of age, sex, or race.
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