Cataract: Definition and Overview

What is cataract?

A cataract is a cloudy lens in the eye that may cause vision problems. The lens is the part of the eye that focuses light on the retina, which in turn translates the light into the impulses transmitted to the brain.

What are the symptoms of cataract?

Cataract is a painless condition. Some signs of a cataract include impaired distance vision, blurring of vision, decreased night vision, sensitivity to glare and bright light, a frequent need for new eyeglasses prescriptions, seeing halos around lights, needing brighter lights to read, and monocular diplopia, or double vision in one eye. A certain type of cataract is associated with a phenomenon some call “gaining second sight,” in which a person with farsightedness is able to see close objects again for a time.

Keep an eye on your vision! Learn about preventive steps and treatments for diabetic retinopathy from retinal specialist Dr. Charles Wykoff. >>

What causes cataracts?

Over 70% of Americans over 65 have at least some clouding of the lens, and 18% to 50% have full-blown cataracts. People with diabetes have a higher risk of developing cataracts in their 30’s or 40’s. Cataracts usually develop slowly with age, possibly due to the effects of free radicals, damaging molecules that can sometimes overwhelm the body’s natural ability to neutralize them. Cataracts may also be present at birth in some cases. They may affect one or both eyes. Besides age and damage caused by free radicals, additional factors that may contribute to cataracts include diabetes, smoking, excessive alcohol consumption, overexposure to the sun, radiation, long-term use of certain steroids, previous eye injuries, and a family history of cataracts.

What is cataract surgery?

Most people with cataracts do not have any vision difficulties. But when cataracts interfere with daily living, the recommended treatment is surgery, often a technique called phacoemulsification. The surgery is performed on an outpatient basis under local anesthesia, may involve an incision as small as an eighth of an inch, and takes less than an hour. If both eyes require surgery, the operation is usually only performed on one eye at a time. The surgery involves removal of the cloudy lens and, in most cases, the implantation of an artificial lens.

Over 95% of people who have cataract surgery note improvement in vision afterward, sometimes as soon as the next day, but it can take up to a month to see the greatest changes. While cataract surgery is a relatively safe and common procedure, complications, including bleeding, inflammation, infection, and retinal detachment, can occur. For this reason, frequent checkups following surgery are necessary.

How to prevent cataracts

Steps to prevent the formation of cataracts include keeping blood sugar levels as close to the normal range as possible, stopping smoking, and wearing wide-brimmed hats and sunglasses that protect against both UVA and UVB when you are out in the sun. An annual dilated eye exam is recommended for people with diabetes because of the greater risk for eye diseases such as glaucoma[1] and retinopathy[2], as well as cataracts, associated with diabetes.

  1. glaucoma: /articles/Diabetes_Definitions/Glaucoma/
  2. retinopathy: /articles/Diabetes_Definitions/Retinopathy/

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