Understanding floaters and flashes
Floaters and flashes are two mild forms of eye disturbance that many people experience, particularly later in life. Floaters are tiny translucent blobs or stick shapes that drift around the eye. Flashes are small flashes or flickers of light. Both may happen because of changes to the vitreous body inside the eye during the natural ageing process.
Although most floaters and flashes are a typical sign of ageing, they can also be a symptom of serious eye damage – talk to your ophthalmologist if you are concerned.
As you age, your eye’s vitreous body changes. The jelly-like substance becomes more liquid, and the lining starts to pull away from the retina – the layer at the back of the eye that absorbs light. Floaters appear because the newly liquid vitreous body retains some chunks of jelly, which cast shadows on the retina as they drift in the liquid.
You may notice floaters more when you look at a blank background or when your eyes are moving quickly. Most are harmless, but, in rare cases, they can be so large that they obscure vision. A sudden onset of new floaters can also signify retinal detachment, a serious problem – so check with your ophthalmologist if this happens.
Treatment for larger floaters
If you have large floaters that affect your vision, you may need surgery to remove them. The procedure, called a vitrectomy, involves draining the vitreous fluid from the eye and replacing it with a saline solution. Any floaters are removed along with the fluid, and the body replaces the vitreous fluid in the weeks after surgery.
However, because this procedure comes with some risks – including retinal detachment and cataract formation – it’s rarely recommended.
When your eye is young, the jelly-like vitreous body is firmly attached to the retina. During ageing, the vitreous body shrinks, pulling away from the retina. This pulling and tugging can cause tiny flashes of light to appear in your eye. They may be more evident in the dark and only last for a fraction of a second.
Posterior vitreous detachment
In about 50% of cases, the vitreous body completely pulls away from the retina. This is called posterior vitreous detachment (PVD) and is usually harmless. You may see several larger flashes along with a large floater when it happens. This doesn’t usually affect vision – the larger floaters should shrink or disappear over time.