Cataracts

August 18, 1999
Web posted at: 12:08 PM EDT (1608 GMT)

In this story: Description Risk Symptoms Treatment Prevention RELATEDS

From WebMD

DESCRIPTION

A cataract occurs when a portion of the eye's lens, which is normally transparent, becomes cloudy. It is not known exactly what causes cataracts, although researchers do know that their development is associated with changes in the chemical composition of the eye's lens. Cataracts prevent light from passing through the lens to the light-sensitive cells of the retina at the back of the eyeball. Because the lens is responsible for one-third of the eye's focusing power, cataracts can severely impair a person's ability to see.

RISK

Cataracts are a natural part of the aging process and can occur in one or both eyes. Between the ages of 52 and 64, you have a 50 percent chance of developing a cataract. Cataracts generally don't begin to affect vision, however, until after age 65. By age 75, almost everyone has a cataract, and by 85 nearly half the population has lost some degree of vision as a result.

Several other factors also influence the development of cataracts and may cause them to appear at an earlier age. These include: diabetes; family history of cataracts; eye injury; use of certain medications such as steroids, diuretics or major tranquilizers, such as phenothiazines; excessive alcohol use; smoking; and excessive exposure to sunlight.

SYMPTOMS

People with cataracts typically have hazy or blurred vision. They may also experience sensitivity to light and glare. This may be more pronounced in bright sunlight or while driving at night. Other symptoms include weakened long-distance vision and the need for brighter lighting while reading or doing other close-up work. People with cataracts may also find themselves blinking more in an attempt to clear their vision. Cataracts can be detected through a routine eye exam.

TREATMENT

In the early stages, it may be possible to combat the vision changes brought on by cataracts with frequent updates to your eyeglass prescription. As cataracts progress, however, surgery is the only treatment option.

Cataract surgery is a quick, outpatient procedure that has a success rate of more than 90 percent. In rare cases, side effects such as bleeding, swelling, infection or detached retina occur. If you have cataracts in both eyes, the operation is performed on one eye at a time.

There are two types of cataract surgery. In the first, extracapsular extraction, the surgeon removes the hard center of the lens. The softer, surrounding portions are then vacuumed out. A newer technique, phacoemulsification (commonly called "phaco"), uses sound waves to break up the cataract. The resulting debris is vacuumed out in this procedure as well. This technique needs a smaller incision than extracapsular extraction. In both of these surgeries, the eye's natural lens is replaced with a clear plastic substitute known as an intraocular lens (IOL).

PREVENTION

Research points to a link between cataracts and exposure to ultraviolet light. To protect yourself, it is a good idea to wear a wide-brimmed hat and sunglasses whenever you are out in the sun. When choosing sunglasses, look for brands that promise 100 percent UVA and UVB filtering. Wraparound glasses provide the most protection. A darker lens or higher price tag does not necessarily indicate more filtering power.

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