Perhaps there are more misunderstandings about cataracts than any other condition of the eye. Many people are frightened and fear that they are going to lose their sight, but understanding what a cataract is helps to offer reassurance of what can be done.


  • Cataracts usually form slowly with a gradual blurring of vision. They usually develop as part of the normal aging process but they can be formed as a result of injury to the eye. Cataracts can be present from birth.
  • Cataracts are more common in people with diabetes and can develop at an earlier age than in the general population.
  • Cataract cannot be caused by overuse of the eyes and ‘resting’ the eyes will not stop cataracts from developing or getting worse.
  • There is no known prevention for cataracts.

What is cataract?
In a normal eye the lens behind iris and pupil is clear and transparent but when a cataract forms the lens becomes cloudy or opaque. This prevents light that passes through the pupil from reaching the retina and the image or picture on the retina is fuzzy and blurred.

Cataracts usually develop in adult life, caused by the normal aging process in which the lens becomes harder and cloudy. As this happens there may be a need to have new, stronger glasses more frequently but when the cataract worsens stronger glasses will not improve vision.

Surgery is usually very successful in most people and is performed when the vision has dropped to the point where it is interfering with daily activities. Even though cataracts usually form in both eyes, the surgery is carried out on each eye at different times with the worst eye being treated first.

What is involved in the surgery?
The surgery is usually carried out without an overnight stay in hospital. Most cataract operations are carried out under local anaesthetic and the ophthalmologist performs the operation with a microscope. The lens is removed through a tiny hole in the cornea and a permanent clear plastic lens is implanted. Occasionally very fine stitches are used to close the wound and these may be painlessly removed later. The implanted plastic lens corrects the vision of the eye but many people still need reading glasses after the operation.

Note: for some people a plastic lens implant is not suitable in which case a contact lens is fitted or special glasses are prescribed some weeks after the operation to remove the lens.

After the surgery

  • After the operation the eye will be covered for protection for up to a day but it is advisable to wear the protective eye shield in bed for a month after the operation.
  • Eyelids must be cleaned regularly and drops are given to prevent infection and help to reduce any post-operative inflammation. The drops may be necessary for two months after surgery.
  • Rubbing or touching the eyes should be avoided.
  • There may be sensitivity to light and dark tinted glasses are useful.
  • It is advisable to avoid heavy work or lifting but people not in strenuous occupations should be able to return to work couple of weeks after surgery.
  • The eye takes a few weeks to settle down and you will be advised when it is time to have an eye test for new glasses.