What is a cataract?

 

Inside our eyes, we have a natural lens. The lens bends (refracts) light rays that come into the eye to help us see. The lens should be clear. But if you have a cataract, your lens has become cloudy. It is like looking through a foggy or dusty car windshield. Things look blurry, hazy or less colorful with a cataract.

In the normal eye, a clear lens allows light to focus properly on the retina.

What are symptoms of a cataract?

Here are some vision changes you may notice if you have a cataract:

  • Having blurry vision
  • Seeing double (when you see two images instead of one)
  • Being extra sensitive to light
  • Having trouble seeing well at night, or needing more light when you read
  • Seeing bright colors as faded or yellow instead

What causes cataracts?
Aging is the most common cause of cataracts. This is due to normal eye changes that happen after around age 40. That is when normal proteins in the lens start to break down. This is what causes the lens to get cloudy. People over age 60 usually start to have some clouding of their lenses. However, vision problems may not happen until years later.
Other reasons you may get cataracts include:

In an eye with a cataract, light scatters throughout the eye instead of focusing properly on the retina.

  • having parents, brothers, sisters, or other family members who have cataracts
  • having certain medical problems, such as diabetes
  • having had an eye injury, eye surgery, or radiation treatments on your upper body
  • having spent a lot of time in the sun, especially without sunglasses that protect your eyes from damaging ultraviolet (UV) rays

Most age-related cataracts develop gradually. Other cataracts can develop more quickly, such as those in younger people or those in people with diabetes. Doctors cannot predict how quickly a person’s cataract will develop.

How are cataracts treated?
Cataracts can be removed only with surgery. If your cataract symptoms are not bothering you very much, you don’t have to remove a cataract. You might just need a new eyeglass prescription to help you see better. You should consider surgery when cataracts keep you from doing things you want or need to do.

Left, normal vision. At right, dull or yellow vision.

How does cataract surgery work?
During cataract surgery, your eye surgeon will remove your eye’s cloudy natural lens. Then he or she will replace it with an artificial lens. This new lens is called an intraocular lens (or IOL). When you decide to have cataract surgery, your doctor will talk with you about IOLs and how they work.

People who have had cataract surgery may have their vision become hazy again years later. This is usually because the eye’s capsule has become cloudy. The capsule is the part of your eye that holds the IOL in place. Your ophthalmologist can use a laser to open the cloudy capsule and restore clear vision. This is called a capsulotomy.

Blurry or dim vision

Cataracts are a very common reason people lose vision, but they can be treated. You and your ophthalmologist should discuss your cataract symptoms. Together you can decide whether you are ready for cataract surgery.

You may be able to slow down your development of cataracts.
Protecting your eyes from sunlight is the best way to do this. Wear sunglasses that screen out the sun’s ultraviolet (UV) light rays. You may also wear regular eyeglasses that have a clear, anti-UV coating. Talk with your eye doctor to learn more.

Summary
When you have a cataract, your eye’s naturally clear lens is cloudy. Eventually your vision will be hazy and blurry. The only way to remove a cataract is with surgery. With cataract surgery, your cloudy lens is replaced with an artificial lens. You do not have to have cataract surgery if your symptoms are not too bad. You should consider surgery when cataracts keep you from doing your daily activities.

You may be able to slow the development of cataracts by protecting your eyes from the sun. It is important to see your ophthalmologist regularly to check for eye and vision changes. If you have any questions about your vision, speak with your ophthalmologist. He or she is committed to protecting your sight.

Watch a cataract video from the American Academy of Ophthalmology’s EyeSmart program below.

« Previous     Next »