Overview
The eye is filled with a clear gel. As it ages it liquefies and shrinks, and strands of collagen within it cast shadows on the retina. Those are floaters. When the gel tugs on the retina as it pulls away, the retina fires, and you see a flash.
Most floaters are a normal part of ageing and the brain learns to ignore them. The distinction that matters is sudden change: a new shower of floaters, or new flashes, can mean the retina has torn.
What are the common symptoms?
- Specks, threads, rings or cobwebs drifting across vision
- More noticeable against a bright plain background
- Movement that lags behind your eye
- Brief arcs or streaks of light, usually in peripheral vision and often worse in the dark
What causes it, and who is at risk?
- Age-related liquefaction of the vitreous gel
- Posterior vitreous detachment, most commonly between 50 and 70
- High myopia, which brings it forward by a decade or more
- Previous cataract surgery or eye injury
- Inflammation inside the eye, or bleeding from diabetic retinopathy
How is it treated?
Established, stable floaters usually need nothing but an explanation and a baseline examination.
- A dilated retinal examination to rule out a tear — the essential step
- Reassurance and time; most floaters become less noticeable over months
- Laser to seal any tear found
- Vitrectomy in rare, severely disabling cases
- A follow-up exam a few weeks later, since some tears appear after the first episode
When to get seen quickly
Seek same-day care for a sudden increase in floaters, any new flashing lights, or a shadow or curtain in your field of vision.
This page is general information, not a diagnosis. Only an eye care professional who has examined you can tell you what is actually going on.