A cataract is clouding of the lens inside the eye. It usually develops slowly and people experience a gradual change in vision. A cataract may cause blurry vision, problems with glare and haloes (seen as rings around lights), and a change in your colour vision.
Are there different kinds of cataract?
Yes. The most common type are age-related, but certain conditions, medications, eye injuries and other eye problems may also contribute to cataract development. Babies can also be born with cataracts. This is called congenital cataract.
Deciding to have cataract surgery
When the cataract progresses to a point where it is interfering with daily activities and normal lifestyle, cataract surgery can be considered. If the cataract is not removed, your vision may stay the same, or it may get worse.
The purpose of the operation is to replace the cloudy lens (cataract) with an artificial lens (implant) inside your eye. If you have your operation under local anaesthetic, you will be awake during the operation. Your head will be supported with a pillow and your eye held open with a clip. You will be aware of a bright light. You will be given eye drops before the operation to enlarge the pupil and to numb the eye. You may also need an injection near the eye.
During the operation you will be asked to keep your head still and lie as flat as possible. The operation usually takes around 30 minutes. Most cataracts are removed by a process called phacoemulsification. This technique uses the latest technology in which sound waves soften the cataract, which is then removed by tube, through a tiny cut in the eye. Your eye is never removed and replaced during cataract operations.
Will I see better?
The vast majority of patients have improved vision within 4 weeks from their cataract surgery, although most people still require reading glasses. If you have another condition, such as diabetes, glaucoma, age-related macular degeneration or a lazy eye, your quality of vision may be limited even after successful surgery.
Benefits and Risks of cataract surgery
Cataract surgery is one of the most successful operations. Most people experience an improvement in clarity of vision and improved colour vision. The focussing power of your eye will be different and therefore your glasses prescription will be different. There is a 95% chance of better vision following surgery. However, as with all surgery, there are risks involved.
1 in 10 chance of a minor complication, which may require further outpatient appointments
1 in 100 chance of a major complication, which may require a further operation
1 in 1000 chance of loss of vision
Possible complications during the operation
Tearing of the back part of the lens capsule with disturbance of the eye jelly, which may result in reduced vision.
Loss of all or part of the cataract into the back of the eye requiring a further operation and possibly a general anaesthetic
Bleeding inside the eye
Possible complications after the operation
Bruising of the eye or eyelids
High pressure inside the eye
Clouding of the cornea
Allergy to eye drops
Common questions about Cataracts
No. But often they develop in both eyes at the same time.
No. Cataracts are not caused by overuse of the eyes and using the eyes when a cataract starts to develop will not make the cataract worse.
There may be a need to get new prescriptions for glasses more often when a cataract is developing. When the cataract worsens, however, stronger glasses no longer improve sight. Objects have to be held close to the eye to be seen. The hole in the iris (pupil) may no longer look black; a white or yellow appearance may be seen. The lens behind the pupil becomes more dense and cloudy (opaque) as the cataract develops.
Some people may not be aware that a cataract is developing. It can start at the edge of the lens and initially may not cause problems with vision. Generally, as a cataract develops, people experience blurring or hazing of vision. Often they become more sensitive to light and glare.
There is no known prevention for cataracts. Modern surgery is highly successful for the majority of patients.