What Is a Cataract?

A cataract is a cloudy area in the lens of the eye.

A normal lens is clear. It lets light pass to the back of the eye. A cataract blocks some of the light. As a cataract develops, it becomes harder for a person to see.

Cataract is a normal part of aging. About half of Americans ages 65 to 74 have cataract. About 70 percent of those age 75 and over have this condition.

Most people with cataract have a cataract in both eyes. However, one eye may be worse than the other because each cataract develops at a different rate.

Some people with cataract don't even know it. Their cataract may be small, or the changes in their vision may not bother them very much. Other people who have cataract cannot see well enough to do the things they need or want to do.

This booklet can help you decide what to do if you have a cataract. Talk about it with your eye doctor so you can make the choices that are right for you.

What Are the Symptoms of Cataract?

Here are some signs of cataract:

• Cloudy, fuzzy, foggy, or filmy vision.
• Changes in the way you see colors.
• Problems driving at night because headlights seem too bright.
• Problems with glare from lamps or the sun.
• Frequent changes in your eyeglass prescription.
• Double vision.
• Better near vision for awhile only in farsighted people.

These symptoms also can be signs of other eye problems.

See your eye doctor to find out what you have and how it can be treated.

A regular eye exam is all that is needed to find a cataract. Your eye doctor will ask you to read a letter chart to see how sharp your sight is. You probably will get eye drops to enlarge your pupils (the round black centers of your eyes). This helps the doctor to see the inside of your eyes. The doctor will use a bright light to see whether your lenses are clear and to check for other problems in the back of your eyes.

Other eye tests may also be used occasionally to show how poorly you see with cataract or how well you might see after surgery:

• Glare test.
• Contrast sensitivity test.
• Potential vision test.
• Specular photographic microscopy.

Only a few people need these tests.

How is Cataract Treated?

A change in your glasses, stronger bifocals, or the use of magnifying lenses may help improve your vision and be treatment enough. The way to surgically treat a cataract is to remove all or part of the lens and replace it with an artificial lens.

Just because you have a cataract does not mean it must be removed immediately. Cataract surgery can almost always be put off until you are unhappy with the way you see.

Your eye doctor will tell you whether you are one of a small number of people who must have surgery. For example, your doctor may need to see or treat an eye problem that is behind the cataract. Or surgery may be required because a cataract is so large that it could cause blindness.

How Do I Decide Whether To Have Surgery?

Most people have plenty of time to decide about cataract surgery. Your doctor cannot make your decision for you, but talking with your doctor can help you decide.

Tell your doctor how your cataract affects your vision and your life. Check (X) the statements below that apply to you and share this list with your doctor:

• I need to drive, but there is too much glare from the sun or headlights.
• I do not see well enough to do my best at work.
• I do not see well enough to do the things I need to do at home.
• I do not see well enough to do things I like to do (for example, read, watch TV, sew, hike, play cards, go out with friends).
• I am afraid I will bump into something or fall.
• Because of my cataract, I am not as independent as I would like to be.
• My glasses do not help me see well enough.
• My eyesight bothers me a lot.

You may also have other specific problems that you want to discuss with your eye doctor.

What Should I know About Surgery?

Your doctor will discuss the options with you before choosing the best kind of cataract removal and lens replacement for you. He or she will also explain how to prepare for surgery and how to take care of yourself after it is over.

Most people do not need to stay overnight in a hospital to have cataract surgery. You may go to an outpatient center or hospital, have your cataract removed, and leave when your doctor says you are fit to leave. However, you will need a friend or family member to take you home. You also will need someone to stay with you for at least a day to help you follow your doctor's instructions.

It takes a few months for an eye to heal after cataract surgery. Your eye doctor should check your progress and make sure you have the care you need until your eye recovers fully.

Can a Cataract Return?

A cataract cannot return because all or part of the lens has been removed. However, in about half of all people who have extracapsular surgery or phacoemulsification, the lens capsule becomes cloudy. This cloudiness of the lens capsule, if it occurs, usually develops a year or more after surgery. It causes the same vision problems as a cataract does.

The treatment for this condition is a procedure called YAG capsulotomy. The doctor uses a laser (light) beam to make a tiny hole in the capsule to let light pass. This surgery is painless and does not require a hospital stay.

Most people see better after YAG capsulotomy, but, as with cataract surgery, complications can occur. Your doctor will discuss the risks with you. YAG capsulotomy should not be performed as a preventive measure.

Is Cataract Surgery Right for Me?

Most people who have a cataract recover from surgery with no problems and improved vision. In fact, serious complications are not common with modern cataract surgery. This type of surgery has a success rate of 95 percent in patients with otherwise healthy eyes. But no surgery is risk free. Although serious complications are not common, when they occur they could result in loss of vision.

If you have a cataract in both eyes, experts say it is best to wait until your first eye heals before having surgery on the second eye. If the eye that has a cataract is your only working eye, you and your doctor should weigh very carefully the benefits and risks of cataract surgery.

You will be able to make the right decision for yourself if you know the facts. Ask your doctor to explain anything you do not understand. There is no such thing as a "dumb" question when it comes to your health.

Here are some questions you might ask:

• Do I need surgery right away?
• If not, how long can I wait?
• What are my personal risks?
• What benefits can I expect?
• If I choose surgery, which type is best for me?
• Which lens replacement is best for me?
• What are the chances of developing cloudiness in the lens capsule after cataract surgery?
• What are the benefits and risks of YAG capsulotomy?

You may wish to write down other questions to ask your doctor to help you make an informed decision about treatment:

Benefits and Risks of Cataract Surgery

How Can I Learn More About Cataract?

Organizations that can provide additional information include:

• American Academy of Ophthalmology
• P.O. Box 7424
• San Francisco, CA 94120-7424
• Phone: (415) 561-8500
• American Optometric Association
• Communications Center
• 243 North Lindbergh Boulevard
• St. Louis, MO 63141-7881
• Phone: (314) 991-4100
• National Eye Institute
• National Institutes of Health
• Bethesda, MD 20892
• Phone: (301) 496-5248
• National Society to Prevent Blindness
• 500 East Remington Road
• Schaumburg, IL 60173
• Phone: toll free 800-331-2020

For Further Information

The information in this booklet was based on the Clinical Practice Guideline on Cataract in Adults: Management of Functional Impairment. The guideline was developed by an expert panel sponsored by the Agency for Health Care Policy and Research. Other guidelines on common health problems are available, and more are being developed.

For more information on guidelines or to receive more copies of this booklet, call toll free 800-358-9295 or write to:

• Agency for Health Care Policy and Research
• Publications Clearinghouse
• P.O. Box 8547
• Silver Spring, MD 20907

Figures

Side view of eye

Side view of eye with artificial lens

AHCPR Publication No. 93-0544.

National Library of Medicine DOCLINE Information: CAT/9423479