Cataracts

Overview

A cataract is a cloudy area in the lens of your eye; the clear part of the eye that helps focus light. This cloudiness can cause vision loss in one or both eyes. A cataract cannot spread from one eye to the other.

Cataracts are very common in older adults. In fact, more than half of all Americans age 80 or older either have cataracts or have had surgery to get rid of them.

The lens of your eye is made mostly of water and protein. The protein is arranged in a precise way that keeps the lens clear and lets light pass through it. As we age, some of these proteins may clump together and cloud the lens. Over time, this cloudy area may grow and cover more of the lens, making it harder to see.

Surgery can get rid of cataracts, and cataract surgery is safe and corrects vision problems caused by cataracts.

Image

Signs and Symptoms

Symptoms might not be noticeable at first, when cataracts are mild. But as they grow, cataracts can cause changes in vision. At first, vision may become blurry, as if looking through a foggy window.

Common symptoms include:

• Cloudy or blurry vision
• Colors that look faded
• Poor night vision
• Lamps, sunlight, or headlights that seem too bright
• A halo around lights
• Double vision in one eye (this sometimes goes away as the cataract develops)
• Frequent changes to your eyeglasses or contact lenses prescription

Image

Age-related cataracts can affect vision in two ways: Clumps of protein reduce the sharpness of the image reaching the retina. The clouding may become severe enough to cause blurred vision. Cataracts tend to “grow” slowly, so vision gets worse gradually. Additionally, the clear lens slowly changes to a yellowish or brownish color, adding a brownish tint to vision. If you have advanced lens discoloration, you may not be able to identify blues and purples.

Because cataracts make it harder for the eye to focus light on the retina, the optic nerve cannot send clear signals to the brain, that is why your vision is blurry, hazy, or less colorful when you have cataracts.

Talk with your eye doctor if you have any of these symptoms, as they could also be signs of other eye problems.

Related Health Effects

Cataracts are one of several age-related eye diseases and conditions that can lead to vision loss and blindness in older adults.

Other conditions include:

• Age-related macular degeneration (AMD), which can harm the sharp, central vision needed to see objects clearly and to do common things like driving and reading
• Glaucoma, which is usually caused by too much pressure inside the eye and can lead to vision loss and blindness if not treated

Even small changes in sight can increase your risk of falls and injuries.

Causes and Risk Factors

Cataracts form when the proteins in the lens of your eye clump together, making your lens cloudy. After age 40, the proteins in the lens naturally start to break down, and most cataracts happen because of these natural changes.

Your risk for cataracts goes up as you get older. You are also at higher risk if you:

• Have certain health problems, like diabetes
• Smoke
• Drink too much alcohol
• Have a family history of cataracts
• Had an eye injury, eye surgery, or radiation treatment around the eye
• Spent a lot of time in the sun, especially without sunglasses
• Take steroids to treat health problems like arthritis or allergies

Prevention Guidance

You can take steps to protect your eyes from cataracts:

• Protect your eyes from the sun. Wear sunglasses and a hat with a brim to block ultraviolet rays from the sun.
• Protect your eyes from injury. While doing activities like using power tools or playing certain sports, wear protective eyewear.
• Quit smoking. If you are ready to quit, call 1-800-QUIT-NOW (1-800-784-8669) for free support.
• Make eye-healthy food choices. Eat plenty of healthy foods — like fruits and vegetables, leafy greens, nuts, and whole grains.
• Limit alcohol use. Drinking too much alcohol can make cataracts form faster.

Researchers believe good nutrition can help reduce the risk of age-related cataract, and they recommend eating green leafy vegetables, fruit, and other foods with antioxidants.

If you are age 60 or older, you should have a comprehensive dilated eye exam at least once every 1 to 2 years. In addition to cataracts, 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.

Diagnosis

An eye doctor can check for cataracts.

A comprehensive dilated eye exam includes:

• Visual acuity test: This eye chart test measures how well you see at various distances.
• Dilated eye exam: Drops are placed in your eyes to widen, or dilate, the pupils. Your eye care professional uses a special lens to examine your retina and optical nerve for signs of damage and other eye problems.
• Tonometry: An instrument measures the pressure inside the eye. Numbing drops may be applied to your eye for this test.

Your eye care professional may also do other tests to learn more about the structure and health of your eyes.

Treatment and Management

Surgery is the only way to get rid of cataract, but you may not need to get surgery right away.

Early on, you may be able to make small changes to manage cataracts:

• Use brighter lights at home or work.
• Wear anti-glare sunglasses.

New Glasses or Contacts

A new prescription for eyeglasses or contact lenses can help you see better with cataracts early on.

Surgery

Your doctor might suggest surgery if your cataracts start getting in the way of everyday activities like reading, driving, or watching TV. During cataract surgery, the doctor removes the clouded lens and replaces it with a new, artificial lens — also called an intraocular lens, or IOL. 9 out of 10 people who get cataract surgery can see better afterward.

Your doctor might also recommend surgery even if your cataracts are not the main cause of your vision problems. You may need to have cataracts removed so your doctor can see into the back of your eye to track and treat other conditions, like diabetic retinopathy or age-related macular degeneration (AMD).

Most people do not need to rush into surgery. Waiting to have surgery usually will not harm your eyes or make surgery more difficult later.

What Happens Before Surgery?

About a week before surgery, your eye doctor will do some tests to measure the size and shape of your eye. These tests help your doctor choose the right type of artificial lens.

What Happens During Surgery?

Usually, you will be awake during cataract surgery. Your eye doctor will:

• Put numbing drops into your eye to keep you from feeling anything.
• Use tiny tools to cut into your eye, break up the lens, and take it out.
• Place the new artificial lens in your eye.

Most people who have cataract surgery can go home the same day. You will need someone to drive you home.

What Happens After Surgery?

Itching and mild discomfort are normal after cataract surgery. Your eye may be sensitive to light and touch. After 1 or 2 days, moderate discomfort should disappear. In most cases, healing will be complete within 8 weeks.

Possible Complications

Problems after surgery are rare, and with prompt medical attention they usually can be treated successfully.

Secondary Cataracts

After cataract surgery, some people may develop a secondary cataract, or posterior capsule opacification that your eye doctor can fix with laser treatment, a procedure called a YAG (Yttrium Aluminum Garnet) laser capsulotomy, which is done as an outpatient.

Living With Cataracts

If you have lost some vision, speak with your eye doctor about surgery to treat your cataract.

After surgery, your eye doctor will give you eye drops to help your eye heal.

Some people notice that colors seem brighter after cataract surgery, because the artificial lens does not have the noticeable yellow or brown tint the natural lens had from the cataract.

Find Clinical Trials

Clinical trials uncover better ways to prevent, diagnose, treat, and understand diseases and conditions. To ensure results apply to everyone, volunteers of all ages, sexes, and backgrounds, including both healthy individuals and those with specific medical conditions, are needed. Find clinical trials on cataracts.

Community Support

The following organizations can provide information and support:

• American Society of Cataract and Refractive Surgery
• American Academy of Ophthalmology
• www.eyecareamerica.org (Online Referral)
• American Optometric Association
• Prevent Blindness
• American Foundation for the Blind
• Vision Aware — American Printing House for the Blind

Note: This resource list is for informational purposes only. It is not comprehensive, and an organization’s inclusion does not constitute an endorsement by NIH.  

Research Information

The National Institutes of Health (NIH) is the largest public funder of biomedical research in the world. NIH invests most of its budget in medical research seeking to enhance life and to reduce illness and disability. NIH-funded research has led to breakthroughs and new treatments helping people live longer, healthier lives, and building the research foundation that drives discovery.  

NIH conducts and supports a number of studies focusing on factors associated with the development of age-related cataracts. These studies include:

• The effect of sunlight exposure, which may be associated with an increased risk of cataract
• Genetic studies, which show promise for better understanding cataract development

NIH also funds research on new treatments for cataracts.

Find NIH-funded research projects using NIH RePORTER, a searchable database of current and past research projects supported by NIH and other federal agencies.