Floaters — the dots, threads, cobwebs or shadows that drift across your visual field — are extremely common. For most people, they are a normal part of ageing. But a sudden increase in floaters, or floaters accompanied by flashes of light, can occasionally be the first sign of a retinal tear or retinal detachment: conditions that require urgent treatment to preserve sight.
What causes floaters?
The eye is filled with a gel called vitreous humour. As we age, the vitreous gradually liquefies and collapses, often pulling away from the back of the eye in a process called posterior vitreous detachment (PVD). As the vitreous moves, tiny clumps of collagen cast shadows on the retina — these are what you see as floaters.
PVD is extremely common, affecting most people over the age of 60, and is usually harmless. The floaters often become less noticeable over weeks to months as the brain adapts.
When floaters and flashes are a warning sign
As the vitreous peels away from the retina, it occasionally pulls hard enough to tear the retinal tissue. A retinal tear allows fluid to pass underneath the retina, which can lead to retinal detachment — a medical emergency requiring surgery.
- A sudden shower of new floaters (particularly if they look like 'smoke' or a cloud of dots) — may indicate bleeding from a torn retinal vessel.
- Flashes of light — caused by the vitreous tugging on the retina. Often described as lightning streaks or a flickering in peripheral vision.
- A dark shadow, curtain, or veil over part of your vision — this is a retinal detachment until proven otherwise.
- A sudden reduction in central vision — can indicate involvement of the macula.
What to do if you get sudden new floaters or flashes
Do not wait. Same-day dilated fundus examination by an ophthalmologist or optometrist with retinal imaging is required. If you develop a visual shadow or curtain, go directly to your nearest eye casualty — do not drive yourself.
In West Yorkshire, the eye casualty is at Huddersfield Royal Infirmary. Alternatively, go to your nearest A&E and ask for an urgent ophthalmology review.
Treatment of retinal tears
If caught at the tear stage (before detachment), treatment is laser retinopexy — a quick outpatient laser procedure that welds the retina around the tear, sealing it. This procedure typically takes around 15 minutes and is very effective.
Once retinal detachment has occurred, surgery is needed — either vitrectomy or scleral buckling — and the visual outcome depends heavily on whether the central part of the retina (the macula) was involved before surgery.
Long-standing floaters with no other symptoms
If you have had the same floaters for months or years with no change, no flashes, and no shadow over your vision, they are very likely benign. They rarely disappear entirely but most people find them less bothersome over time. Vitrectomy surgery to remove floaters is available privately but is reserved for cases where floaters cause significant, ongoing visual disability, given the small but real surgical risks involved.
Frequently Asked Questions
I suddenly have a lot more floaters than usual. Should I go to A&E?
A sudden increase in floaters — especially if accompanied by flashes of light, a shower of dark spots, or any shadow in your peripheral vision — warrants same-day ophthalmological assessment. Do not wait overnight. If your vision is also affected or you see a shadow/curtain, go to eye casualty or A&E immediately.
Can floaters be treated or removed?
Most floaters do not require treatment and become less noticeable over time. For significant, vision-disrupting floaters in an otherwise healthy eye, pars plana vitrectomy can remove them. This is effective but carries small risks (retinal detachment, cataract, infection) so is only recommended when floaters cause meaningful daily visual impairment.
Are flashes of light in my vision always serious?
Not always. Flashes caused by vitreous traction on the retina during a posterior vitreous detachment are very common and usually harmless — but they do require a dilated eye examination to confirm the retina is intact. Flashes associated with migraine (a spreading, shimmering arc that lasts 20–30 minutes, usually without a shadow or floaters) are a different phenomenon and generally harmless.
Mr Mohamed Mohyudin
MBChB BSc MSc FRCOphth CCT — Consultant Ophthalmic Surgeon, Spire Elland Hospital, Yorkshire. GMC 7039600.
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