Those squiggly lines drifting across your vision are almost certainly eye floaters, tiny clumps of collagen fiber inside the gel-like fluid that fills your eyeball. They’re extremely common, generally harmless, and become more frequent as you age. Most people notice them when looking at a bright, plain background like a blue sky or white wall.
How Floaters Form Inside Your Eye
Your eyeball is filled with a clear, jelly-like substance called the vitreous. It’s mostly water, but it gets its gel texture from a network of microscopic collagen fibers. As you age, this gel gradually liquefies and shrinks, a process called syneresis. When that happens, collagen fibers that were once evenly distributed start to clump together into tiny strands or knots.
These clumps float freely inside the liquefying gel. When light enters your eye, the clumps cast shadows on the retina (the light-sensitive layer at the back of your eye), and your brain interprets those shadows as shapes. That’s why floaters can look like squiggly lines, threads, cobwebs, rings, or small dark spots. They seem to dart away when you try to look directly at them because the fluid shifts whenever your eye moves, carrying the clumps along with it.
Age and Nearsightedness Are the Biggest Risk Factors
Age is the primary driver. The vitreous gel starts breaking down gradually in middle age, and the process accelerates over time. By ages 50 to 59, about 24% of people have experienced a posterior vitreous detachment (PVD), a more advanced stage where the shrinking gel pulls away from the retina entirely. By ages 80 to 89, that figure climbs to 87%. A PVD often produces a sudden burst of new floaters, sometimes accompanied by brief flashes of light.
Nearsightedness (myopia) is the other major risk factor, and it’s the leading cause of bothersome floaters in younger people. Nearsighted eyes are longer than average, which stretches the vitreous and accelerates the breakdown of its collagen structure. If you’re significantly nearsighted and noticing floaters in your 20s or 30s, this is likely why.
Other factors that can increase your risk include eye injuries, prior eye surgery (especially cataract removal), and inflammation inside the eye.
Floaters vs. Migraine Visual Disturbances
Not all “squiggly lines” are floaters. Migraine auras, sometimes called scintillating scotomas, can produce visual disturbances that look very different but might lead you to the same search. The key differences are easy to spot once you know what to look for.
Migraine auras typically appear as shimmering, flickering, or sparkling patches in your vision. People describe them as looking like heat ripples rising off hot pavement, or like peering through a kaleidoscope. They often form rings, arcs, jagged zigzag lines (called fortification patterns), or even checkerboard shapes. These disturbances expand or shift over 20 to 60 minutes, then fade completely.
Floaters, by contrast, are grey or translucent, don’t shimmer or flash, and drift with your eye movements rather than expanding on their own. They also don’t go away after a set time period. If what you’re seeing sparkles, pulses, or forms geometric patterns, you’re more likely experiencing a migraine aura than a floater.
When Floaters Signal Something Serious
A few floaters that you’ve had for months or years are almost never a problem. What matters is sudden change. The National Eye Institute identifies three warning signs that require prompt evaluation:
- A sudden increase in floaters, especially many new ones appearing at once
- Flashes of light in one or both eyes
- A shadow or “curtain” creeping over part of your field of vision
These symptoms can indicate a retinal tear or retinal detachment, where the retina pulls away from the back of the eye. This is a medical emergency. Without treatment, a detached retina leads to permanent vision loss. If you experience these symptoms together, get your eyes examined the same day.
Diabetes is another cause worth knowing about. In advanced diabetic retinopathy, damaged blood vessels in the retina can leak blood into the vitreous. A small bleed produces what looks like a sudden shower of dark spots or floaters. A larger bleed can cloud your vision significantly or block it entirely. If you have diabetes and notice new floaters, don’t wait to have it checked.
How Floaters Are Diagnosed
An eye care provider checks for floaters using a dilated eye exam. You’ll receive drops that widen your pupil, giving the provider a clear view of the vitreous and the retina behind it. The exam itself takes about 20 to 30 minutes, though your vision will stay blurry for a few hours afterward from the dilation drops. This allows the provider to see whether the floaters are simple collagen clumps, or whether there’s a retinal tear, detachment, or bleeding that needs treatment.
Do Floaters Ever Go Away?
Most floaters don’t disappear, but they do become less noticeable over time. Your brain gradually learns to tune them out through a process called neuroadaptation. This filtering effect varies from person to person, but most people reach maximum adaptation within three to six months of noticing new floaters. After that, you may only notice them in specific lighting conditions.
For the majority of people, no treatment is needed. You simply stop seeing them as your brain adjusts. However, some people develop floaters dense enough to genuinely interfere with reading, driving, or daily tasks.
Two treatment options exist for severe cases: a laser procedure that breaks up the collagen clumps, and a surgical procedure called vitrectomy that removes the vitreous gel entirely and replaces it with a saline solution. Both carry risks, and there are currently no randomized clinical trials comparing the two head to head. That means doctors don’t have strong evidence to recommend one over the other, so treatment decisions tend to be made case by case based on the size, location, and severity of the floaters. Most ophthalmologists reserve these procedures for floaters that significantly impair quality of life.
Practical Ways to Cope
While you wait for neuroadaptation to do its work, a few simple adjustments can help. Floaters are most visible against bright, uniform backgrounds, so wearing sunglasses on sunny days reduces how often you notice them. Adjusting the brightness on your computer screen or switching to a slightly off-white background in documents can also help. When a floater drifts into your line of sight, quickly looking up and then back down can shift the vitreous fluid and move the clump out of the way temporarily.