What Are Cataracts?

A cataract is a clouding of the lens of the eye that can impair vision. More than half of all Americans age 65 and older have cataracts in their eyes.

What Causes Cataracts?

The eye acts much like a camera. Light rays enter through the front of the eye. They pass through the cornea, the pupil, and the transparent fluid in the front of the eye — onto the lens. The lens then bends light rays to focus objects onto the retina in the back of the eye. From there, the retina, the optic nerve, and the brain take the images and form vision.

Cataracts occur when there is a buildup and change in the protein in the lens that makes it cloudy. This keeps light from passing through the lens causing some loss of vision. The lens is supposed to be clear to have good vision. No one knows what causes the buildup of protein. The cataract is a lens that has become clouded.

Types of cataracts:

• Age-related cataracts. As the name suggests, this type of cataract develops as a result of aging.
• Congenital cataracts. Babies are sometimes born with cataracts as a result of an infection they had before they were born, or cataracts may develop during childhood.
• Secondary cataracts. These may develop as a result of other diseases, like diabetes, or long-term exposure to toxic substances, certain medications (such as corticosteroids), ultraviolet light, and radiation.
• Traumatic cataracts. These can form after injury to the eye.

Other factors that can increase a person's risk of cataracts include cigarette smoke, air pollution, and heavy use of alcohol.

What Are The Symptoms Of Cataracts?

Cataracts often form slowly and cause few symptoms. When symptoms are present, they can include:

• Vision that is cloudy, blurry, foggy, or filmy
• Rapid advance of nearsightedness
• Changes in the way you see color, especially yellow
• Problems driving at night due to oncoming headlights
• Problems with glare
• Double vision
• Rapid temporary improvement in close-up vision

How Are Cataracts Diagnosed?

Your eye doctor will give you an eye exam to test how well you can see. Remember to bring your glasses or wear your contacts to the appointment. Your doctor will also dilate your pupil in order to look at the condition of the lens and other parts of the eye. The eye exam will help the doctor find out how the cataract has changed your vision.

How Are Cataracts Treated?

If your vision is all right, you may get a prescription for eyeglasses including bifocals and contacts.

If you suffer from vision loss that makes it hard for you to go about your daily life, you may want to discuss cataract surgery. This is surgery that replaces a cloudy lens with a clear plastic one. Cataract surgery is usually done on an outpatient basis and it is usually successful. In fact, it is a common surgery in the US, with more than 1.5 million cataract surgeries done each year. More than 9 out of 10 people who have this surgery have improved vision.

Talk to your eye doctor to see which treatment is right for you.

Can Cataracts Be Prevented?

Because we don't know the exact cause of cataracts, there is no proven way of preventing them. But since they are so common in older adults, you need to have your eyes checked on a regular basis. The American Academy of Ophthalmology says that people aged 40 to 64 should have a complete eye exam every 2 to 4 years. People 65 and older should have one every 1 to 2 years.