What are floaters?
Floaters are opacities in the vitreous gel of the eye, which is normally otherwise clear. These shifting opacities cast shadows on the retina, which are perceived as floaters.
What usually causes floaters?
A few floaters can develop in young adulthood and are usually nothing to worry about. Between the ages of around 40-75 years, people can sometimes develop sudden onset of floaters (sometimes with fleeting flashes of light in the outside of their field of vision). This process is called PVD (posterior vitreous detachment) and all patients with these symptoms should undergo detailed examination of the retina in order to exclude a retinal break or retinal detachment.
Can anything else cause floaters?
Occasionally, inflammatory eye disease (uveitis) can cause floaters, although there are often other symptoms and signs of this. Very rarely, floaters can be a sign of a serious malignancy affecting the eye and/or brain, known variously as CNS / vitreoretinal / intraocular lymphoma.
Do I need to see anybody about my floaters?
If you have had floaters for years and your symptoms are not changing, a sinister or sight-threatening cause is extremely unlikely and you need not consult anybody. If you have experienced
- recent or sudden onset floaters
- floaters with pain or eye redness
- floaters along with reduction in your vision, or a shadow in your vision
you ought to have a detailed eye and/or retinal examination and should see your GP or optometrist as soon as possible in order to be referred for this.
I have been reassured that my floaters are not serious, but they are annoying me – can they be treated?
Floaters can be removed with an operation known as vitrectomy. The success of vitrectomy at removing bothersome floaters is very high (over 95%), although as with any operation, the surgery carries rare risks including loss of vision. Most patients who develop acute floaters do not need surgery because they become less bothersome with time. If however your floaters have been present for more than 3-4 months and are still causing troublesome symptoms, you may be considered for vitrectomy.
Are there any alternatives to surgery for floaters?
The only alternative treatment is to fire Nd:YAG laser shots at the floaters, but this generally just breaks a small number of large floaters into multiple smaller ones, which are often just as troublesome to the patient. It is perhaps noteworthy that most proponents of laser treatment for floaters are usually not trained to perform pars plana vitrectomy. Conversely, very few trained vitreoretinal surgeons offer laser treatment as their first choice intervention for floaters. The laser treatment may occasionally be attempted, however, in select patients who for medical reasons cannot undergo an eye operation – for example patients who cannot lie down reasonably flat on an operating table and who are willing to take the risk that their floaters may persist or symptomatically worsen.