Cataract
A cataract is a clouding of the lens in your eye. It affects your vision. Cataracts are very common in older people. By age 80, more than half of all people in the United States either have a cataract or have had cataract surgery.
Common symptoms are
- Blurry vision
- Colors that seem faded
- Glare
- Not being able to see well at night
- Double vision
- Frequent prescription changes in your eye wear
Cataracts usually develop slowly. New glasses, brighter lighting, anti-glare sunglasses or magnifying lenses can help at first. Surgery is also an option. It involves removing the cloudy lens and replacing it with an artificial lens. Wearing sunglasses and a hat with a brim to block ultraviolet sunlight may help to delay cataracts.
Cataracts are classified as one of three types:
- A subcapsular cataract begins at the back of the lens. People with diabetes, high farsightedness, retinitis pigmentosa or those taking high doses of steroids may develop a subcapsular cataract.
- A nuclear cataract is most commonly seen as it forms. This cataract forms in the nucleus, the center of the lens, and is due to natural aging changes.
- A cortical cataract, which forms in the lens cortex, gradually extends its spokes from the outside of the lens to the center. Many diabetics develop cortical cataracts.
Cataract Symptoms and Signs
A cataract starts out small and at first has little effect on your vision. You may notice that your vision is blurred a little, like looking through a cloudy piece of glass or viewing an impressionist painting.
A cataract may make light from the sun or a lamp seem too bright or glaring. Or you may notice when you drive at night that the oncoming headlights cause more glare than before. Colors may not appear as bright as they once did.
The type of cataract you have will affect exactly which symptoms you experience and how soon they will occur. When a nuclear cataract first develops, it can bring about a temporary improvement in your near vision, called “second sight.” Unfortunately, the improved vision is short-lived and will disappear as the cataract worsens. On the other hand, a subcapsular cataract may not produce any symptoms until it’s well-developed.
What Causes Cataracts?
No one knows for sure why the eye’s lens changes as we age, forming cataracts. Researchers are gradually identifying factors that may cause cataracts — and information that may help to prevent them.
Many studies suggest that exposure to ultraviolet light is associated with cataract development, so eyecare practitioners recommend wearing sunglasses and a wide-brimmed hat to lessen your exposure.
Other types of radiation may also be causes. For example, a 2005 study conducted in Iceland suggests that airline pilots have a higher risk of developing nuclear cataract than non-pilots and that the cause may be exposure to cosmic radiation. A similar theory suggests that astronauts, too, are at risk from cosmic radiation.
Other studies suggest people with diabetes are at risk for developing a cataract.
The same goes for users of steroids, diuretics and major tranquilizers, but more studies are needed to distinguish the effect of the disease from the consequences of the drugs themselves.
Some eyecare practitioners believe that a diet high in antioxidants, such as beta-carotene (vitamin A), selenium and vitamins C and E, may forestall cataract development. Meanwhile, eating a lot of salt may increase your risk.
Other risk factors include cigarette smoke, air pollution and heavy alcohol consumption.
A small study published in 2002 found lead exposure to be a risk factor; another study in December 2004, of 795 men age 60 and older, came to a similar conclusion.
But larger studies are needed to confirm whether lead can definitely put you at risk and, if so, whether the risk is from a one-time dose at a particular time in life or from chronic exposure over years.*
Cataract Treatment
If you are diagnosed with a cataract, there are other treatment options that can be considered before surgery to replace your clouded lens. Cataract treatment consists of both non-surgical methods of improving symptoms of vision deterioration as well as surgical removal of the cataract. You and your eye doctor should develop a cataract treatment plan based on the type and severity of your cataracts. Below are several methods of cataract treatment.
Non-surgical Cataract Treatment
Early cataract treatment is aimed at improving your quality of vision. When cataract symptoms appear, you may experience cloudy or blurry vision, light sensitivity, poor night vision, double vision, and changes in your eyewear prescription. Certain changes can significantly reduce these symptoms.
Cataract symptoms may be improved with new eyeglasses, anti-glare sunglasses, or magnifying lenses. Certain tints and coatings can also be added to lenses to reduce symptoms. Even better positioning of lamps or reading lights can help. Your eye doctor may recommend that you wear a hat when outdoors in addition to qualitysunglasses to help prevent further cataract development.
Certain lifestyle changes may improve your vision enough to delay cataract surgery. Surgical removal of cataracts is recommended when your vision loss interferes with everyday activities, such as driving, reading, or watching TV. However, it is very important that your cataract treatment plan includes proper counseling regarding the impact of reduced vision. For example, if your vision is reduced significantly, even with best corrected prescription, you should be advised of the many risks associated with driving and operating large equipment or machinery. If one eye has a significant cataract and the other eye does not, you may lack the ability to accurately judge distances. If your doctor does not discuss this with you, ask him to.