What is a cataract?
A cataract is any clouding or opacity in the crystalline lens - the normally transparent lens inside the eye. A cataract is not a tumor or growth of skin over the eye. Having a cataract does not mean you will necessarily have to do anything about it or that you will eventually be blinded by it.
What causes a cataract?
Most cataracts occur as part of the aging process, from a change in the chemical composition of the lens. They usually do not become a problem until you are in your 60s or 70s. (If you live long enough, you are almost certain to develop one eventually.) Some, but not all, scientists feel that prolonged exposure (over years) to sunlight can damage the lens and plays a role in cataract development.
Cataracts can also be caused by eye injuries, certain eye diseases and body conditions, hereditary or birth defects, and occasionally, some medications. They are not caused or made worse by using or "overusing" the eyes.
How can I tell if I have a cataract?
You may have noticed a gradual blurring or dimming of vision. Some people see a "halo" or haze around lights, especially at night, or have hazy or double (or multiple) vision. At first, the symptoms may only occur in dim light or when you face bright oncoming car headlights; the glare may make night driving especially difficult. Pain headaches and eye irritations are not usually symptoms of cataracts.
Is it possible to have a cataract and not notice it?
Yes. If the cataract is small, it may not disturb your vision or cause any symptoms at all. Even a dense cataract may not be noticed if the other eye is providing clear vision. In fact, you might not be aware of the blurred vision unless you happened to cover the normal eye. Unless it is very dense, a cataract is not visible to the naked eye of an observer.
Once a cataract begins, how rapidly does it progress?
No one can predict how fast a cataract will develop. Generally, the clouding of the lens progesses slowly and gradually over a period of months or years. It is not known why some cataracts progress rapidly and others progress slowly.
What is the treatment for cataracts?
At present, the only effective treatment is surgical removal of the cloudy lens. This can be done in a hospital or outpatient surgical suite. Some studies hint that the process can be slowed by vitamin C or aspirin, but other treatments, such as medications or exercises, do not help at all.
If the cataract is minimal, treatment may be delayed for a while by changing your glasses prescription or by dilating (enlarging) your pupils.
How successful is the surgery in restoring sight?
About 95%. It is one of the most effective and safest operations performed today. The high success rate is due to advances in microscope technique, high-tech instruments, ultrafine needles and suture materials, and use of intraocular lenses.
What causes the 5% failures?
They do not obtain clear eyesight after the surgery for a variety of reasons. Some have pre-existing disease affecting the retina or optic nerve that prevents normal sight; others have one of the rare complications of cataract surgery.
What are the complications of cataract surgery?
Though rare, infection, bleeding, glaucoma, corneal problems, chronic intraocular inflammation, and retinal detachment are possible. Most of the complications, if they do occur, are usually temporary or can be treated successfully with medication; rarely, they require a second surgical procedure.
When should a cataract be removed?
Whenever it interferes with your vision so much as to make a difference in your life or livelihood. Since everyone's visual needs differ, this point will differ from one person to another. It is not necessary to wait until the cataract is "ripe" (totally opaque) before having it removed.
Who makes the decision about when a cataract is to be removed?
You do. You will be advised that you are a candidate for the surgery and what kind of improvement in vision you can expect from a cataract removal that is free of complications. You will then have to decide if the cataract is causing you enough trouble to warrant surgery (there is no need to remove a cataract until it significantly interferes with vision). There are certain rare circumstances that require cataract removal regardless of vision; if it becomes overly mature("overripe"), if it begins to release chemicals that can damage the eye, if it contributes to glaucoma, or if it prevents observation or treatment of other eye diseases.