Cataracts are a very common cause of sight problems in older people, but a simple operation can cure them. Dan Parton reports.

In this article:

  • What are cataracts?
  • Symptoms
  • Treatments
  • Monitoring

What are cataracts?

Cataracts are the main cause of vision impairment world-wide and are especially prevelant in developing countries. Men and women are equally affected.

Cataracts are a common form of sight problems in older people; it said to affect more than 50% of UK over 65s in one or both eyes.

Like in cameras, the lens is a transparent cover over the eye. A cataract is when part of the lens becomes clouded. As a result, light cannot pass through as easily to the retina at the back of the eye, which makes it more difficult to see images in sharp focus.

Over time, the clouding becomes bigger and/or more of them develop, making vision increasingly blurred and cloudy.


Cataracts can take many years to develop and in the early stages symptoms are not noticeable.

The exact causes of cataracts are not known, although some studies have linked smoking, excessive exposure to sunlight and poor diet with cataract development.

Sometimes cataracts are caused by other health problems such as diabetes. A history of cataracts in your family would also increase your risk of them.

The most common symptom of a cataract is that gradually vision becomes cloudy, misty or blurred. In addition, small spots or dots can appear in the line of vision where sight is not as clear, colour may appear faded or washed out and bright lights, such as headlamps, can become dazzling. It can also become more difficult to see in dim light.

As a result, reading, watching TV and other daily activities may become more difficult than they used to be. People that wear glasses may also find that they become less effective over time. As the cataracts become more severe, it will begin to affect the sufferer’s daily life and their ability to look after themselves.


When cataracts are in the early stages of development, stronger glasses or using brighter lights can help. Likewise, a good diet can help to slow the development of cataracts.

But these measures only temporarily slow the progression of the cataract(s) and they will gradually continue to worsen. If left untreated, cataracts ultimately will result in blindness.

When cataracts reach the point where the loss of vision affects a person’s daily activities and ability to look after themselves, the only treatment is to have an operation to remove the cloudy lens.

The operation involves the lens being replaced with an artificial clear plastic lens, known as an intraocular implant or intraocular lens. This lens stays permanently in the eye and there is no chance of it being rejected.

Approximately 10 million lens replacement operations are conducted world-wide every year. The operation is not major; it takes about 15-30 minutes and most are done as keyhole surgery under local anaesthetic. The majority of patients do not need to stay in hospital overnight.

Complications after an operation are rare – fewer than 2% have unforeseen problems – and most of these, such as a thickening of the lens casing, can be easily corrected.

Many people notice an instant improvement in vision after the operation, although it can take several months to heal fully and for vision to settle down. Eye drops will need to be taken for a couple of months after the operation.

Patients may still need to wear glasses, although those who wore glasses for short-sightedness before the operation may find that their prescription changes afterwards because the new lens can be set up to correct this.

If cloudy vision returns quickly, it’s possible the patient may have developed a condition called Posterior Capsule Opacification (PCO).


Unfortunately nothing can be done to prevent Cataracts although as mentioned, a good diet can slow their development.

Therefore it is important that older people have regular eye tests – at least once every two years – even if they do not have to wear glasses, because then cataracts are more likely to be picked up early. Opticians routinely check for cataracts in an eye test and can detect them before the sufferer has noticed any symptoms.