The short answerFloaters are small dots, threads or cobwebs that drift as your eye moves. They are usually caused by normal changes in the vitreous, the gel that fills the eye, and most are harmless. But a sudden shower of new floaters, new flashes of light, or a shadow or curtain over part of your vision can mean a retinal tear or detachment, and you need a dilated eye exam the same day.
What are floaters?
The inside of the eye is filled with a clear gel called the vitreous. Over time part of it turns liquid and its fibres clump together. These clumps cast shadows on the retina, which you see as dots, threads or rings that move when you move your eye. They show up most against a clear sky, a white wall or a bright screen.
Posterior vitreous detachment
With age the vitreous shrinks and pulls away from the retina at the back of the eye. This is called a posterior vitreous detachment. It is common and normal in most people, and it happens earlier in short-sighted people and after eye surgery or injury. It can cause new floaters and lightning-like flashes at the edge of your vision, because the gel tugs on the retina as it separates.
Most of the time the vitreous separates without causing harm. In some people, though, it pulls hard enough to make a small tear in the retina. If that tear is not treated, fluid can pass through it and lift the retina off, which is a retinal detachment and a threat to sight.
Warning signs: get seen the same day
- A sudden shower of new floaters, like a cloud of specks.
- New flashes of light, especially if they keep coming or increase.
- A shadow or dark curtain over part of your vision, from any side.
- A sudden drop in vision.
- Any of these after a blow to the eye or head.
Do not wait for symptoms to settle on their own. A retinal tear found early can often be sealed with laser or freezing treatment in the clinic, before it becomes a detachment that needs surgery.
How is it checked?
The doctor puts in drops to widen your pupils and then examines the whole retina out to its edges. The drops leave your vision blurred and sensitive to light for several hours, so do not drive afterwards. You may be asked to come back for a second check a few weeks later, because a tear can appear some time after the symptoms start.
Can floaters be treated?
No eye drop, medicine or vitamin dissolves floaters. Most people get used to them within weeks to months as the brain learns to ignore them, and they often settle lower in the eye where they are less noticeable. In the rare cases where floaters seriously interfere with vision, a doctor may discuss surgery, which carries its own risks and is only offered after careful assessment.
Frequently asked questions
Are eye floaters dangerous?
Most are not, especially old floaters that have not changed. The concern is a sudden burst of new floaters, or floaters with flashes or a curtain over your vision. That needs a retina check the same day.
Are there eye drops that get rid of floaters?
No. No drop or medicine dissolves them. Most people get used to them over time, and surgery is kept for a very small number of cases after a doctor's assessment.
What are lightning flashes in the corner of my eye?
They are usually the vitreous tugging on the retina. This is often a normal vitreous detachment, but only a dilated exam can rule out a retinal tear, so new flashes should be checked promptly.
Does short-sightedness make floaters more likely?
Yes. Short-sighted people tend to have a vitreous detachment earlier and have a higher risk of retinal tears, so they should pay particular attention to the warning signs.