What is a cataract?
A cataract is not a skin that grows over your eyes, but a cloudiness of the lens itself in the eye. The lens in the eye focuses light on to the retina to produce a clear image. As we get older the lens changes, from being transparent, becoming yellow and then progressively darker in colour. During this process the lens becomes less transparent and opaque areas develop. This causes blurring of the vision making reading, driving, watching television and using computer screens difficult. This is the process of cataract formation. Cataract development may be asymmetrical so that one eye may be more affected that the other.
What are the symptoms of cataract?
- Blurred vision
- Colours appear muted, often with a yellow hue
- Difficulty reading fine print
- Frequent changes required to your spectacle prescription
- Glare or dazzle, particularly with bright sunlight or oncoming headlights
What causes cataracts?
Cataracts are usually natural results of ageing but may occur in younger people for a variety of reasons including:
- Injury to the eye
- Following surgery to the eye, especially retinal surgery
- Diseases such as diabetes or glaucoma
- After prolonged inflammation of the eye
- Occasionally there may be a family history of cataract
When should a cataract be removed?
Cataracts can take many years to develop and in the early stages no treatment may be required, other than a change in spectacle prescription. However, if the symptoms start to affect normal activities it may be necessary to consider an operation to remove the cataract and replace it with an artificial lens implant. This will then allow the light to pass through to the back of the eye again, without the filtering effect of the cataract. A cataract does not need to be “ripe” before surgery. This phrase refers back to a time, many years ago, when cataracts were only taken out when they were extremely dense. The timing of cataract surgery varies from person to person and Mr McLean will discuss with you the advantages and disadvantages of cataract surgery at any particular time.
How is the cataract removed?
Cataract surgery is usually performed as a day case using local anaesthetic. This doesn’t preclude the use of sedation or general anaesthetic, which is necessary for some people. A tiny self-sealing incision is made on the surface of the eye. The cloudy lens is removed by phacoemulsification where ultrasound is used to fragment the cataract and remove it. An artificial lens implant is then placed in the eye, through the small incision. The lens is flexible and can be rolled into a cylinder, allowing it to be injected into the eye through the small incision. The lens then unfolds automatically and moves into position within the lens capsule or bag.
Are there any risks?
Cataract surgery is a remarkably successful procedure in most cases. However, as with any other operation small risks do exist. The most significant risks are of infection, bleeding inside the eye, risk of retinal detachment and even loss of vision in very rare cases. When you see Mr McLean he will discuss the operation in more detail, together with the benefits and risks of cataract surgery. He will answer any questions you might have as well as discussing which type of anaesthetic would be best suited for you.
Complicated cataract surgery
It can be more difficult to remove some types of cataract. Many factors can influence the surgery, such eyes which are very short sighted or long sighted, conditions which affect the amount of room within the eye in which to operate. Other factors can affect the stability of the lens, making it difficult or impossible to insert the lens into the lens coating or bag, which is the usual choice. A different location or a different type of lens is used in these cases. If any of these factors apply to your eyes then Mr McLean will discuss these points with you.
Download the pdf below for more information about what to do in the days after your cataract operation.