Symptoms & Causes
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.
Risk factors for developing cataracts include advanced aged, family history, diabetes, obesity, smoking, high blood pressure , long term steroid use, and previous eye surgery. If you have any of these risk factors for cataracts, you should schedule an appointment with your ophthalmologist.
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 occur only in dim light or when you face bright oncoming car headlights; the glare may make night driving especially difficult. You may also have difficulty distinguishing colors, reading small print, and performing normal daily activities such as cooking and cleaning. Pain, headaches, and eye irritation are not usually symptoms of cataract.
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 progresses slowly and gradually over a period of months or years. It is not known why some cataracts progress rapidly and other progress slowly.
For more information visit the American Academy of Ophthalmology's website.