Eye floaters: what are they and what do they mean?

Have you ever wondered what the squiggly lines that sometimes cross your vision really are? From time to time, most of us will experience these eye floaters – small specks or shapes, often like cobwebs that seem to dart away when we try to see them more clearly. Mr Vaughan Tanner, an expert ophthalmologist is here to explain what floaters really are and why it is worth getting them checked out.

What is an eye (vitreous) floater?

The appearance of eye floaters within the vision is usually due to age-related changes in the vitreous gel which naturally fills the eye. This gel degenerates and shrinks over time and this can cause stringy clumps to form, which cast shadows on the retina. We perceive these shadows as floaters. In most patients over the age of 50 there is some visible degeneration causing clumping of the collagen fibres, which may occasionally interfere with vision.

What causes eye floaters?

As the gel degenerates further it peels away from the retina, a process called posterior vitreous detachment (PVD). This second stage of degeneration causes additional floaters and debris together with descriptions of intermittent blur or a veil like effect in the vision. People often describe blobs, circles or a fly-like shape together with flashes of light in the vision. The flashes are due to pulling on the retina by the vitreous gel. It is this pulling which occasionally causes retinal tears and retinal detachment.

Are eye floaters dangerous?

In the vast majority of patients eye floaters are a minor irritation with no need for treatment. However, it requires urgent specialist examination to exclude underlying serious disease which can damage vision. It is particularly important that anyone noticing sudden new floaters should be seen urgently to exclude a retinal tear which can progress to retinal detachment and sight loss. It is impossible to know just on symptoms whether a tear is present.

When do eye floaters become serious?

If the floaters are associated with a retinal tear or retinal detachment then this can usually be treated with laser or a vitrectomy surgery to prevent visual loss, but requires an urgent visit to an eye doctor with a special interest in retinal disease.

Do they ever go away?

In the majority of patients, floater symptoms improve over a period of approximately six months but may never entirely disappear. If symptoms persist and cause problems, for example with driving or reading, then there are treatments available.

What is YAG laser vitreolysis of eye floaters?

Laser treatment has improved significantly in recent years, with much better laser focusing allowing safer treatment. Laser is particularly effective at treating discrete dense floaters, which it can vaporise, making them disappear. It is very difficult to remove all floaters and debris but approximately 90% of patients report significant improvement in their vision and feel the procedure was worthwhile.

Can I have vitrectomy for eye floaters?

In patients with significant symptoms who are not suitable for laser treatment then vitrectomy surgery is available to remove the vitreous gel and floaters. Vitrectomy surgery is very effective at removing almost all floaters and these are some of my happiest patients. However, vitrectomy does carry significant risk and there needs to be a careful discussion prior to surgery to ensure floaters are causing sufficient problem to justify surgery.