What are cataracts?

A cataract is defined as clouding or loss of transparency in the lens of the eye that interferes with vision. Cataracts usually develop as a result of normal aging and are most prevalent in people over 40, with half of all people in the U.S. developing cataracts by the age of 80 (Source: NEI).

The lens is formed of water and special proteins that are initially clear. Cataracts develop when proteins of the lens begin to cluster and become denser. The formation of these protein bundles makes it difficult for light to pass through the eye to the retina and creates a discolored or opaque area in the lens.

Less commonly, cataracts may occur at any age as a result of injury to the lens. In some cases, cataracts are congenital, which means they are present at birth. Cataracts may also develop as a result of diabetes or extended use of certain medications, including corticosteroids. Cataracts due to aging, disease, or drugs tend to occur in both eyes, although the degree of severity may be different in the two eyes. A cataract caused by trauma will affect only the injured eye.

Cataracts generally develop over time and may get progressively worse as you age. In most cases, you most likely will not experience any symptoms until the cataract is advanced. Symptoms include gradually increasing haziness of vision and glare or halos from lights. Cataracts are not treated until they cause visual symptoms. Fortunately, cataract surgery is highly successful in restoring clear sight.

Cataracts generally do not indicate a medical condition that needs immediate attention. However, they can be a sign of chronic serious conditions such as diabetes. Seek prompt medical care if you have symptoms of cataracts that become bothersome or are associated with other symptoms.


What are the symptoms of cataracts?

Cataracts are painless, and they produce only visual symptoms. If you have symptoms in any other part of your body along with cataracts, they are not caused by the cataracts. But they may be related to underlying diseases such as diabetes that can also play a role in the development of cataracts.

Visua... Read more about cataractssymptoms


What causes cataracts?

Cataracts develop when proteins in the lens, which are normally clear, begin to clump or aggregate. This process causes discoloration and loss of transparency in the lens. Eventually, the loss of transparency interferes with the passage of light rays through the lens to the retina, and vision becomes cloudy.

In most cases, cataract formation occurs as a result of aging. However, i... Read more about cataractscauses


How are cataracts treated?

Cataracts are generally not treated until they begin to affect your vision noticeably. Some minor symptoms of cataracts, including dulling of vision or small changes in visual acuity, may be improved by nonsurgical approaches such as improved lighting or changes in eyewear prescriptions.

Once your cataracts begin to interfere with your ability to drive at night, read, or watch TV,... Read more about cataractstreatments

Medical Reviewer: William C. Lloyd III, MD, FACS Last Annual Review Date: Aug 9, 2013 Copyright: © Copyright 2014 Health Grades, Inc. All rights reserved. May not be reproduced or reprinted without permission from Health Grades, Inc. Use of this information is governed by the HealthGrades User Agreement.

This Article is Filed Under: Eyes and Vision

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