EYE CONDITIONS

CATARACTS

A cataract is a clouding of the internal lens of the eye that affects vision. Normally, the lens is clear, like glass. Light rays pass through the lens and are focused onto the retina in the back of the eye. If the lens becomes cloudy, light can no longer pass through freely and vision is no longer clear. Most cataracts are related to aging, and are very common in older people. By age 80, more than half of all Americans either have a cataract or have had cataract surgery. A cataract can occur in either or both eyes; however, it cannot spread from one eye to the other.

Causes of Cataracts

Cataracts are caused by a change in the lens itself. The lens is made of mostly water and protein. The protein is arranged in a precise way that keeps the lens clear and lets light pass through it. But as we age, some of the protein may clump together and start to cloud a small area of the lens. This is a cataract. Over time, the cataract may grow larger and cloud more of the lens, making it harder to see. Cataracts can also result from direct injury to the eye, from certain eye inflammations and sometimes are associated with diseases that affect the whole body, such as diabetes. Radiation and some medications, especially steroids, may cause cataracts. Even steroids used in nasal sprays for asthma can accelerate cataract formations. Also, some children are born with cataracts.

How Cataracts Affect Vision

Age-related cataracts can affect your vision in two ways:

1. Clumps of protein reduce the sharpness of the image reaching the retina. Cataracts tend to "grow" slowly, so vision gets worse gradually. Over time, the cloudy area in the lens may get larger, and the cataract may increase in size. Seeing may become more difficult. Your vision may get duller or blurrier.
2. The clear lens slowly changes to a yellowish/brownish color, adding a brownish tint to vision. Over time, increased tinting may make it more difficult to read and perform other routine activities. This gradual change does not affect the sharpness of images; however, if you have advanced lens discoloration, you may not be able to identify blues and purples.

Symptoms of Cataracts

The most common symptoms of a cataract are:

• Cloudy or blurry vision
• Colors seem faded
• Glare from headlights, lamps or sunlight, or a halo may appear around lights
• Poor night vision
• Double vision or multiple images in one eye - although, this symptom may clear as the cataract gets larger
• Frequent prescription changes in your eyeglasses or contact lenses

Risk Factors

The risk of cataract increases as you get older. Other risk factors for cataract include, certain diseases such as diabetes, personal behavior such as smoking and alcohol use, and the environment such as prolonged exposure to sunlight.

Treatment of Cataracts

The symptoms of early cataract may be improved with new eyeglasses, brighter lighting, anti-glare sunglasses or magnifying lenses. If these measures do not help, surgery is the only effective treatment. Surgery involves removing the cloudy lens and replacing it with an artificial lens. The lens of the eye has about 18 diopters of focusing power. When the cataractous lens is removed, this power must be restored. This is generally achieved through an intraocular lens (IOL). Cataract surgery is usually successful in restoring good vision, unless a person has other unrelated eye diseases.

A cataract needs to be removed only when vision loss interferes with your everyday activities, such as driving, reading or watching TV. You and your eye care professional can make this decision together. In most cases, delaying cataract surgery will not cause long-term damage to your eye or make the surgery more difficult. Sometimes a cataract should be removed even if it does not cause problems with your vision. For example, a cataract should be removed if it prevents examination or treatment of another eye problem, such as age-related macular degeneration or diabetic retinopathy.

Cataract surgery is one of the most commonly performed procedures performed in the U.S. Modern surgical techniques make a cataract operation and recovery relatively easy for the patients. It also is one of the safest and most effective types of surgery. Discomfort is usually minor and the patient returns home the same day. In about 90 percent of cases, people who have cataract surgery have better vision afterward.

Protecting Against Cataracts

Once a cataract has developed, there is no medication that can be taken to dissolve it. The only way to restore vision once a cataract has formed is to remove the clouded lens. Cataracts cannot be prevented, but research suggests that protection from ultraviolet rays of the sun, specific vitamin supplementation and eating green leafy vegetables high in antioxidants can stall the onset and progression of cataract formation. If you smoke, stop and limit your alcohol intake. If you are age 60 or older, you should have a comprehensive dilated eye exam at least once every two years. In addition to cataract, your eye care professional can check for signs of age-related macular degeneration, glaucoma and other vision disorders. Early treatment for many eye diseases may save your sight.