Treatment may not be needed if:
- you have no symptoms, or
- your sight is only mildly affected.
In the early stages of a cataract, your vision may be improved with stronger glasses or using a brighter light, for example, to read. However, the improvement may not last long. When cataracts are more severe, the only way to treat them is through surgery.
When will cataracts be treated?
Your optician (optometrist) or GP will probably recommend treatment if your loss of vision affects your usual daily activities. For example:
- looking after yourself or someone else,
- driving,
- going out,
- seeing people's faces,
- working,
- reading, or
- watching television.
What is the treatment?
Cataracts are treated by having an operation to remove the cloudy lens in your eye. In most cases, the natural lens is replaced with an artificial clear plastic lens. This is called an intraocular implant or intraocular lens (IOL).
Most cataract operations in the UK are done as keyhole surgery under local anaesthetic. You will not need to stay in hospital overnight - you will probably be admitted as a day patient (day case).
The most common operation is usually called phacoemulsification. Sometimes it may be called phaco extracapsular extraction.
Cataracts cannot be treated with laser surgery.
Before the operation
Your optician or GP will refer you to a specialist eye doctor (ophthalmologist or ophthalmic surgeon) who will assess your eyes and your general health. This is called a pre-operative assessment.
During the assessment, measurements of your eye will be taken, to prepare for the artificial lens that will replace your natural lens.
An appointment will probably be made for your operation to take place in a separate visit.
Just before the operation, drops to widen (dilate) your pupil will be applied to your eye. You will also be given a local anaesthetic. This may be applied to your eye as drops, although sometimes injections in the tissue around the eye may be used instead.
Once the anaesthetic takes effect, you will not be able to feel anything. While the operation is taking place, all you will be able to see is a bright light. You will not be able to see what is happening.
The replacement lens
Different types of replacement lens are available. For example:
- fixed strength lenses (monofocal) - set for one level of vision, usually distance vision,
- multifocal lenses - allow two or more different strengths, such as near and distance vision, and
- accommodating lenses - allow the eye to focus on both near and distant objects, in a similar way to the natural human lens.
Your doctor will discuss with you what type of lens will suit you.
Multifocal and accommodating lenses are not normally available through the NHS. NHS funding for these types of lens will depend on your local primary care trust (PCT). Ask your GP or ophthalmologist what lenses are available in your area. If NHS funding is not available for these types of lenses, you may be able to pay to have them fitted on a private basis.
For information about accommodating lenses, see the 'cautions' section.
How is the operation done?
The doctor makes a very small cut in the surface (cornea) of your eye at the front. The doctor inserts a tiny probe through this cut. The probe breaks up the cloudy lens into tiny pieces using ultrasound. Then the tiny pieces are sucked out of the eye.
Once this is done, the doctor inserts an artificial clear plastic lens through the cut. The lens sits in a little 'pocket' (the lens capsule) to keep it in place. The lens is folded when it is inserted. Once in position, it is allowed to unfold.
The operation usually takes 15-30 minutes, although sometimes it can take slightly longer. You may be given a pad to wear over your eye, to protect it after the operation.
Other operations for age-related cataracts
Two other operations may be performed to remove age-related cataracts, although these are much less common. In manual extracapsular extraction, the doctor makes a slightly larger cut in the eye, and the lens is removed in one piece, rather than being broken up first by ultrasound.
In intracapsular extraction, the lens capsule is removed, as well as the lens. A replacement plastic lens is then sewn into the eye. In some cases, special (aphakic) glasses or contact lenses may need to be worn instead. This type of operation is rare in the UK.
After your operation
For most people, vision improves noticeably straightaway, although it may take a little while to settle down completely. The cut in the eye's surface is so small that it usually heals by itself, although sometimes a small stitch may be needed.
Your doctor will probably advise you to take it easy, for example, by avoiding sports and any vigorous activities. When the operation is done, your plastic lens will be set up for a certain level of vision. After your operation, you will probably need to wear glasses, for example, to see objects that are:
- far away (distance vision), or
- close to you (near vision).
If you wore glasses before, your prescription will probably change. It takes several weeks after the operation for your vision to settle down before your optician can give you a new prescription.
