Cataract surgery is a procedure used to treat cataracts, where changes in the lens of the eye cause cloudy, blurry, or misty vision.

It's the most common operation performed in the UK, with more than 300,000 procedures carried out each year.


Cataracts occur when changes in the lens of the eye cause it to become less transparent. The lens is the crystalline structure that sits just behind your pupil, which is the black circle in the centre of your eye.

When light enters your eye, it passes throughthe transparent layer of tissue at the front of the eye (the cornea) and the lens, which focuses it on the light-sensitive layer of cells at the back of your eye (the retina).

Cataracts sometimes start to develop in a person's lens as they get older (age-related cataracts) ,stopping some of the light reaching the retina. This can affect your vision, making it become increasingly cloudy, blurry, or misty.

Although cataracts are often associated with age, in rare casesbabies are born with cataracts or young children can develop them (childhood cataracts) .

This topic focuses on surgery for adults with cataracts.

When is cataract surgery recommended?

Slightcloudiness of the lens is a normal part of ageing. Significant cloudiness, or cataracts, usually get slowly worse over time. Surgery to remove them is the only way to restore vision.

However, surgeryisn't necessary if your vision isn't significantly affected and you don't have difficulties carrying out everyday tasks.

Cataract surgery is available on the NHS if you're having difficulty with activities such as reading, driving, or looking after someonein your care.

During the operation, the surgeon will make atinycut (incision) in your eye so they can remove the affected lens. After it's been removed, a small plastic lens called an intraocular implant or intraocular lens will be inserted.

If you have cataracts in both eyes, you'll have two separate operations carried out a few weeks apart. This gives the first eye time to heal and time for your visionto return.

This is because artificial lens implants can't focus on a range of different distances.

The surgeon will normally aim for more focused distance vision, with dependence on reading glasses for close up work, although this depends on the strength of your glasses and individual circumstances.

With glasses, most people have a good enough level of vision to be able to drive and carry out everyday activities without any problems.

Your vision may not be restored to normal if you also have another eye condition or in the rare event of a serious complication.

What are therisks and complications?

The risk of serious complications developing as a result of cataract surgery is small.

The most common complication is a condition called posterior capsule opacification (PCO), which can cause your vision to become cloudy again. In PCO, a skin or membrane grows over the back of the lens implant months or years later.

If necessary, PCO can be treated with a simple laser eye surgery procedure to cut away the membrane.

Other risks or complications of cataract surgery are much rarer and can include:

  • tearing of the lens capsule, the "pocket" that holds the lens in place
  • all or some of the cataract dropping into the back of the eye
  • inability to remove all of the cataract or insert a lens implant
  • infection or bleeding in the eye

Most complications that can potentially develop after cataract surgery can be treated with medication or further surgery, and don't usually have a long-term impact on your vision.

However, there's a very small risk around1 in 1,000 of permanent sight loss in the treated eye as a direct result of the operation.


Content supplied by the NHS Website

Medically Reviewed by a doctor on 28 Nov 2016