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Cataract

Cataract — A Threat to Vision What Is a Cataract? Symptoms of Cataracts Types of Cataracts Removal of Cataracts What Is an After-Cataract? Research Safeguard your Vision!

Cataract — A Threat to Vision

Horizontal Section of Left Eye

Note that cataract forms behind the pupil - not on the outside of the eye

Even though medical research and treatment continues to make significant progress in reducing vision loss from cataract, many people through ignorance, fear or misinformation fail to have surgery that could restore vision. As a result, unoperated cataract remains the leading cause of blindness in the world today. Cataract surgery is one of the safest and most successful surgical procedures. Vision improves in about 90 percent of all patients, unless there is a pre-existing problem with the cornea, retina or optic nerve.

What Is a Cataract?

A cataract is simply a clouding of the lens. It’s been described as “like looking through a dirty window.” Hazy areas develop and coalesce to eventually make the lens completely opaque. When this happens (mature cataract) the pupil is white instead of black and the individual is able to see light only.

A cataract is not, as many people believe, a skin growing over the eye. The affected lens is on the inside of the eye and located behind the pupil which normally appears as a small, black hole in the center of the colored part of the eye.

Normally, the lens is transparent and clear. But, because of various factors, such as age, disease or injury, the lens becomes cloudy, loses its transparency and light rays pass through it with difficulty. This, somewhat like the change in transparency of an egg white when it is boiled, can greatly affect an individual’s ability to see.

Symptoms of Cataracts

Some of the most common symptoms of cataracts are:

• Cloudy or blurry vision
• Glare or light sensitivity
• Colors appear to be faded
• Poor night vision
• Frequent changes in eyeglasses or contact lenses.

Types of Cataracts

• Age-related cataract: This is the most common type, which relates to aging. The term “age-related” is a little misleading. You do not have to be a senior citizen to get this type of cataract. People can have an age-related cataract in their 40s and 50s. But during middle age, most cataracts are small and do not affect vision. It is after age 60 that the opacities in the lens become more prevalent.
• Congenital cataract: Infants can be born with cataracts or develop them in childhood. This condition is caused by either heredity or by possible problems during pregnancy, usually during the first three months. If vision is affected, the cataract may need to be removed.
• Secondary cataract: Cataracts can be caused or aggravated by certain other health problems, such as diabetes. Also, cataracts are sometimes linked to steroid use, previously long-term, unprotected exposure to sunlight, smoking or previous eye surgery.
• Traumatic cataract: Cataracts can develop soon after an eye injury, or many years later. When a sharp object like a pin, needle, knife or scissors pointed accidentally penetrates the lens, the injury can cause a cataract. Such penetrating injuries are especially common in children and industrial workers.

Removal of Cataracts

When an early cataract appears, its progress will be carefully watched by your eye care professional. Surgery is usually not recommended until the cataract begins to affect everyday activities, such as driving, reading or watching TV.

There are two primary ways to remove a cataract. They are:

• Phacoemulsification, or phaco. A small incision is made on the side of the cornea. A tiny probe is then inserted into the eye, which emits ultra sound waves that soften and breaks up the cloudy center of the lens so it can be removed by suction.
• Extracapsular surgery. A slightly longer incision is made on the side of the cornea and the hard center of the lens is removed. The remainder of the lens is removed by suction.

There are two steps involved in the cataract surgery: the removal of the cloudy lens and the permanent replacement of a clear, man-made lens, known as an IOL (intraocular lens ). These lenses are available in a variety of designs and optical powers, including optical corrections for near– and far-sightedness and in some particular cases of astigmatism. For people who are not candidates for an IOL implant — possible problems during surgery or diagnosed with other eye diseases — a soft contact lens or eyeglasses with powerful magnification may be suggested.

Lasers are not routinely used in cataract surgery. However, clinical studies and research are ongoing.

What Is an After-Cataract?

Once in a while a part of the natural lens not removed in cataract surgery becomes cloudy, causing possible blurred vision. This is referred to as an “after-cataract,” which can develop months or years later. In a technique, called YAG laser capsulotomy, the eye doctor makes a tiny hole in the lens which lets light pass through. This is not to be considered a reoccurrence of the cataract that was removed.

Research

Vision researchers continue to look for ways to prevent or delay cataracts, as well as the developing new diagnostic tests and treatment techniques. Studies are also being conducted on factors that put people at risk, the role genetics play and the benefits of foods containing certain vitamins and minerals. New and continued clinical studies are being conducted every day.

Safeguard your Vision!

See your eye care professional regularly — at least once every two years — or more often if you are at high risk or your vision gets worse. If a cataract does develop, your eyeglass prescription may be changed or soft contact lenses pre-scribed. When surgery is indicated, you may be referred to a specialist, who will remove the cloudy lens and replace it with a new permanent lens.

For more information please contact:
ILLINOIS SOCIETY FOR THE Prevention of Blindness

407 S. Dearborn St.
Suite 1000
Chicago, IL 60605-1117
(312) 922-8710
FAX: (312) 922-8713
www.eyehealthillinois.org

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Community Health Charities of Illinois
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