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Posterior vitreous detachment

Patient information A-Z

Your eye

The back of the eye is filled with a jelly-like substance called vitreous. This is normally transparent.

illustration of the eye showing the position vitreous in relation to retina, iris, pupil, lens and optic nerve
Illustration of the eye showing the position of the vitreous in relation to retina, iris, pupil, lens and optic nerve

A natural ageing process causes the lining of the vitreous to separate from the retina. When this occurs it is usually quite sudden causing ‘floaters’ to appear in the vision and sometimes an associated ‘arc’ of flashing light at the side of the vision. The light may be quite dim so that it is seen most easily at dusk or in the dark.

When the vitreous has separated from the retina it is known as a posterior vitreous detachment.

Will it affect my vision?

The floaters can be annoying but they are harmless. They usually persist but become less noticeable with time.

The flashing light will usually subside over weeks, but may sometimes last several months.

What treatment will be needed?

No treatment is needed for a posterior vitreous detachment.

What complications could occur?

Occasionally as the vitreous separates it can tear the retina. This may cause some bleeding (vitreous haemorrhage) within the eye, or even a retinal detachment.

This complication is more likely in short sighted people. The ophthalmologist who examined you will have ensured that there is no retinal tear or retinal detachment present at the moment.

What symptoms need to be reported?

- Shower of dot-like floaters
- Loss of vision
- Growing dark shadow from the edge of the vision

If you experience any of these symptoms please contact us immediately:

Emergency Eye Clinic – 01223 217778
Vitreo Retinal Nurses – 01223 274865

Retinal detachment and vitreous haemorrhage (bleeding into the vitreous) are potentially blinding conditions. However timely treatment and surgery is effective in most cases.

For further information on retinal detachment please visit the Vitreoretinal Service website (opens in a new tab).

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Contact us

Cambridge University Hospitals
NHS Foundation Trust
Hills Road, Cambridge

Telephone +44 (0)1223 245151