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Causes of cataracts
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Cataracts
1763 Words4 Pages
Cataracts
What is a cataract? A cataract is a cloudy or opaque area in the normally
transparent lens of the eye. Its effect on vision depends on the extent of the cloudiness.
Small spots in the lens may cause little or no vision loss. As the opacity thickens, it
prevents light rays from passing through the lens and focusing on the retina, the light
sensitive tissue lining the back of the eye. Early lens changes or opacities may not disturb
vision. But as the lens continues to change, several specific symptoms including blurred
vision; sensitivity to light and glare; increased nearsightedness; or distorted images in
either eye, may develop. Cataracts are usually associated with aging. As a person grows
older, the lens becomes less flexible and loses some of its ability to focus light onto the
retina. As the lens becomes harder, it tends to develop cataracts. Cataracts can eventually
become milky white and fill the lens. The patient is then considered blind. Doctors do not
know how to prevent or cure most types of cataracts. But surgery to remove the diseased
lens can improve vision for most cataract patients. After such surgery, some patients.
After such surgery, some patients must wear strong glasses or contact lenses to see well
enough to carry on normal activities. In most cases, however, surgeons replace the
diseased lens with a plastic intraocular lens. A patient who receives an intraocular lens
may or may not need glasses or contact lenses to see well.
Physiology Of A Normal System
The eye normally consist of a lens that is located behind the iris, the colored
portion of the eye, and the pupil, the dark center of the eye. Tiny ligaments, called
zonules, support the lens capsule wi...
... middle of paper ...
...hopefully will help other elderly people
understand the signs and symptoms to look for cataracts and ways that cataracts can be
prevented. About half of Americans between ages 65 and 74, 70% of those older than age
75, have cataracts (Mayo Clinic Health Letter, 1995, 3).
Bibliography:
American Academy of Ophthalmolgy. (1996-1997). Eyenet. Eye Conditions &
Diseases. 1-11, http://www.eyenet.org/public/faqs/cataract/cat_prevention.html.
Larson, D. E. (1996). Mayo Clinic Family Health Book, 2nd Ed. 238-239, 266,
553-556.
Long B., Phipps W., Cassmeyer V. (1993). Medical Surgical Nursing, 3rd Ed.
1313.
Mayo Clinic Health Letter. (Oct. 1995). Vision and Your Eyes. 1-8.
Miller, M. (July 1996). Your Aging Eyes. Better Homes and Gardens. 46, 48,
50-51.
Wilson, K. (March 1996). Weight and See. Prevention. 26, 28, 30.
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