Cataract

The human eye contains a lens that focuses light within the eye. When this lens becomes cloudy it is called a cataract.

Cataract can lead to blurring and mistiness of vision and also to ‘glare’ which is the worsening of vision in bright light. Particularly troublesome examples of glare include dazzle caused by on-coming headlights and worsening of vision in bright sunshine.

Photographs of different
types of cataract

Cataracts can occur as a result of diseases or injury to the eye, but most commonly occur as a result of ageing. Conditions such as diabetes can lead to the early development of cataracts.

The treatment of cataract is by surgery. Cataract surgery is normally performed under local anaesthetic (although some patients prefer general anaesthetic).

During the operation the cataract is broken down into small pieces using high frequency ultrasound (called phaco-emulsification). The pieces are then removed via a tiny incision that is self-sealing (so small it does not require stitches).

A folding acrylic lens is inserted into the eye to replace the cloudy lens.

Surgery usually takes about 20 minutes and the patient is free to leave within 30 minutes of the operation.

By adjusting the strength of the implanted lens, it is often possible to correct long or short sightedness and reduce the need for strong glasses.

Most cataract operations will result in a return to normal vision as long as the eye does not have other eye disease such as macular degeneration.

The correct time for surgery depends very much on how much nuisance the cataract is causing the patient. In addition, some people such as drivers or pilots require a very good level of vision, and may wish to undergo surgery sooner in order to carry on these activities. The old fashioned concept of the cataract having to ‘ripen’ is no longer the case.

Complications of cataract surgery are fortunately uncommon. The most serious complication is infection which can blind the eye, however this complication is rare, occurring only in approximately 1 in 1,000 cataract operations.

Other complications that occasionally occur include dislocation of part of the cataract into the back of the eye, or problems with the retina such as swelling of the retina (macular oedema), retinal detachment or bleeding, all of which require further surgery to correct. As a vitreoretinal surgeon, I specialize in the surgery to correct these complications.