Cataracts

Each year, cataracts affect millions of people, including more than half of all Americans aged 60 and older. A cataract is a painless clouding of the eye's natural lens that is caused by a buildup of protein. A cataract can form in one or both eyes. If left untreated, cataracts worsen over time and interfere with everyday activities such as reading or driving. Night vision is usually most affected. When cataracts are in their early stages, people are helped by brighter lighting. As cataracts get worse, however, most people require surgery.

Risk Factors for Cataracts

In addition to aging, other factors, including the following, can increase the risk of developing cataracts:

Diabetes
Smoking
Obesity
Excessive alcohol use
Excessive exposure to sunlight
Exposure to radiation
Family history of cataracts
High blood pressure
Previous eye injury or surgery
Prolonged use of corticosteroid medications

In rare instances, infants are born with cataracts, which may be the result of an infection, such as rubella, contracted by the mother during pregnancy. They may also occur in combination with some other birth defect. Occasionally, infants develop cataracts shortly after birth.

Diagnosis of Cataracts

Several tests, including the following, are performed to diagnose cataracts:

Retinal examination under pupil dilation
Visual acuity test
Slit-lamp examination
Tonometry to test intraocular pressure (IOP)

In combination, such tests help determine whether a patient has cataracts, or whether her or his vision problems have some other cause. They also assist in evaluating the degree of visual impairment, and whether surgery should be performed.

Symptoms of Cataracts

People with cataracts often do not realize they have them until vision is affected. Cataract symptoms include the following:

Blurred, hazy or double vision in one eye
Decreased color perception
Sensitivity to bright light
Poor night vision
Perception of halos around lights
Frequent changes in corrective-lens prescriptions

Yellow-tinged vision is also an indicator of cataracts.

Treatment of Cataracts

Early cataracts can sometimes be treated with nonsurgical methods, including the following:

New corrective-lens prescriptions
Anti-glare sunglasses
Magnifying lenses
Brighter lighting

If cataracts begin to interfere with reading ability, work, night driving or other daily activities, cataract surgery may be recommended. If cataracts are in both eyes, surgery is performed, usually 4 to 8 weeks apart, on one eye at a time. Cataract surgery is the most common surgical procedure in the United States.

Prevention of Cataracts

Although cataracts cannot be prevented, their development can sometimes be delayed by the following:

Wearing wide-brimmed hats to block sunlight
Wearing sunglasses that block ultraviolet rays
Not smoking; not drinking excessively
Eating a diet high in antioxidants