Eye Floaters

Floaters appear as spots or strands which drift across the vision as the eye moves.

Floaters themselves are harmless and don’t usually interfere with your vision – you may even have them without noticing. This is because your brain constantly adapts to changes in your vision and learns to ignore them.

In a significant minority, floaters can cause disturbances that affect the quality of vision. If this persists, treatment can be offered. However, the first step is establishing the underlying cause.

There are two types of eye floaters:

Long term floaters: usually a symptom of vitreous degeneration and can be very annoying if you suffer with them. They are caused by the break-up of the vitreous jelly which fills the inside of the eye. Vitreous gel is 99% water and 1% clear solids that are present from birth. The solids start to become opaque as the gel degenerates.
Acute floaters: a sudden occurrence of floaters, sometimes associated with flashing lights, may indicate that a posterior vitreous detachment (P.V.D) is occurring which could cause a retinal tear. This in turn could lead to a retinal detachment. Acute floaters should be treated as a medical emergency and professional medical advice should be sought within 24 hours.

Causes of floaters

In the young eye, the vitreous gel is a thin transparent jelly of uniform consistency attached to the eye’s inside wall. As the eye ages, small pockets of liquid vitreous can develop within the gel leaving a ‘carpet’ of jelly over the retina.

These small pockets may develop into large pockets and lead to the gel peeling away. As this happens, the retina may produce light flashes (photopsia) or can sometimes be torn. Light scattering by opacities or blood in the vitreous gel may appear as “floaters”. If a tear occurs and goes untreated, it can eventually lead to retinal detachment.

The appearance of new floaters, along with flashing lights, may indicate a serious retinal problem. This should be treated as a medical emergency with professional medical advice sought within 24 hours.

Symptoms of floaters

Floaters cast shadows on the retina, which is what you can see.

They usually develop as your eyes get older, as part of your natural ageing process.

Common symptoms include:

Small spots or “cobwebs” which flick across the field of vision on eye movement
A generalised mistiness of vision, often described as a fog or mist which may cause glare and increased difficulty in bright light