Post by Ms. Kathy on Apr 23, 2004 5:55:20 GMT -6
[glow=red,2,300]Low Vision and Your Eyes[/glow]
Article from WebMD
Low vision affects 20% of middle-aged adults, but often this condition can be treated or offset by new vision aids, say doctors at The Cleveland Clinic.
Low vision is the loss of sight that is not correctible with prescription eyeglasses, contact lenses, or surgery. Low vision does not include complete blindness because there is still some sight. Often low vision can be improved with the use of visual aids.
Low vision includes different degrees of sight loss from having blind spots, poor night vision, and problems with glare to almost a complete loss of sight. The American Optometric Association defines low vision into two categories:
Partially sighted, meaning the person has visual acuity between 20/70 and 20/200 with conventional prescription lenses
Legally blind, meaning the person has visual acuity no better than 20/200 with conventional correction and/or a restricted field of vision less than 20 degrees wide
The ratio measurement of vision describes visual acuity, or the sharpness of vision, at 20 feet from an object. For example, having 20/70 vision means that you must be at 20 feet to see what a person with normal vision can see at 70 feet.
Anyone can be affected by low vision because it results from a variety of conditions and injuries. Because of age-related disorders like macular degeneration, glaucoma, and cataracts, low vision is more common in adults over age 45 and still even more common in adults over age 75. One in six adults over age 45 have low vision; One in four adults over age 75 have low vision.
The most common types of low vision include:
Loss of central vision: A condition in which a blind spot in the center of one's vision
Loss of peripheral (side) vision: Inability to see anything to either side, above or below eye level. Central vision, however remains intact.
Night blindness: The inability to see in poorly lit areas such as a theater, as well as outside at night
Blurred vision: A condition in which object both near and far appear out of focus
Hazy vision: A condition in which the entire field of vision appears to be covered with a film or glare
What Causes Low Vision?
There may be one or more causes of low vision. Low vision is usually the result of disorders or injuries affecting the eye -- or a condition such as diabetes that affects the entire body. Some of the most common causes of low vision include: age-related macular degeneration, diabetes, and cataracts, but low vision may also result from cancer of the eye, albinism or a brain injury. If you have or are at risk of having these disorders, you are at an increased risk for having low vision.
How Is Low Vision Diagnosed?
An eye exam by your eye care specialist can diagnose low vision. You should make an appointment with your eye doctor if your vision difficulties are preventing you from daily activities like travel, cooking, work, and school. The tests the eye doctor will perform include the use of lighting, magnifiers, and special charts to help test visual acuity, depth perception, and visual field.
Can Low Vision Be Treated?
Some sight disorders, like diabetic retinopathy, can be treated to restore or maintain vision. When this is not possible, low vision is permanent. However, many people with low vision find visual aids helpful. Popular low vision aids include:
Telescopic glasses
Lenses that filter light
Magnifying glasses
Hand magnifiers
Closed-circuit television
Reading prisms
Non-optical aids designed for people with low vision are also very helpful. Some popular non-optical devices include:
Text reading software
Check guides
High contrast clocks and watches
Talking watches and clocks
Large-print publications
Clocks, phones, and watches with enlarged numbers
Visual aids improve both sight and the quality of life for many people. Talk to your doctor about where to purchase visual aids.
Can Low Vision be Prevented?
Low vision may be preventable for patients with diabetes and reversible for those whose vision loss is caused by cataracts.
For more information, see Coping With Vision Loss. Reviewed by the doctors at The Cleveland Clinic Cole Eye Institute.
Edited by Charlotte E. Grayson, MD, Oct. 2003.
Article from WebMD
Low vision affects 20% of middle-aged adults, but often this condition can be treated or offset by new vision aids, say doctors at The Cleveland Clinic.
Low vision is the loss of sight that is not correctible with prescription eyeglasses, contact lenses, or surgery. Low vision does not include complete blindness because there is still some sight. Often low vision can be improved with the use of visual aids.
Low vision includes different degrees of sight loss from having blind spots, poor night vision, and problems with glare to almost a complete loss of sight. The American Optometric Association defines low vision into two categories:
Partially sighted, meaning the person has visual acuity between 20/70 and 20/200 with conventional prescription lenses
Legally blind, meaning the person has visual acuity no better than 20/200 with conventional correction and/or a restricted field of vision less than 20 degrees wide
The ratio measurement of vision describes visual acuity, or the sharpness of vision, at 20 feet from an object. For example, having 20/70 vision means that you must be at 20 feet to see what a person with normal vision can see at 70 feet.
Anyone can be affected by low vision because it results from a variety of conditions and injuries. Because of age-related disorders like macular degeneration, glaucoma, and cataracts, low vision is more common in adults over age 45 and still even more common in adults over age 75. One in six adults over age 45 have low vision; One in four adults over age 75 have low vision.
The most common types of low vision include:
Loss of central vision: A condition in which a blind spot in the center of one's vision
Loss of peripheral (side) vision: Inability to see anything to either side, above or below eye level. Central vision, however remains intact.
Night blindness: The inability to see in poorly lit areas such as a theater, as well as outside at night
Blurred vision: A condition in which object both near and far appear out of focus
Hazy vision: A condition in which the entire field of vision appears to be covered with a film or glare
What Causes Low Vision?
There may be one or more causes of low vision. Low vision is usually the result of disorders or injuries affecting the eye -- or a condition such as diabetes that affects the entire body. Some of the most common causes of low vision include: age-related macular degeneration, diabetes, and cataracts, but low vision may also result from cancer of the eye, albinism or a brain injury. If you have or are at risk of having these disorders, you are at an increased risk for having low vision.
How Is Low Vision Diagnosed?
An eye exam by your eye care specialist can diagnose low vision. You should make an appointment with your eye doctor if your vision difficulties are preventing you from daily activities like travel, cooking, work, and school. The tests the eye doctor will perform include the use of lighting, magnifiers, and special charts to help test visual acuity, depth perception, and visual field.
Can Low Vision Be Treated?
Some sight disorders, like diabetic retinopathy, can be treated to restore or maintain vision. When this is not possible, low vision is permanent. However, many people with low vision find visual aids helpful. Popular low vision aids include:
Telescopic glasses
Lenses that filter light
Magnifying glasses
Hand magnifiers
Closed-circuit television
Reading prisms
Non-optical aids designed for people with low vision are also very helpful. Some popular non-optical devices include:
Text reading software
Check guides
High contrast clocks and watches
Talking watches and clocks
Large-print publications
Clocks, phones, and watches with enlarged numbers
Visual aids improve both sight and the quality of life for many people. Talk to your doctor about where to purchase visual aids.
Can Low Vision be Prevented?
Low vision may be preventable for patients with diabetes and reversible for those whose vision loss is caused by cataracts.
For more information, see Coping With Vision Loss. Reviewed by the doctors at The Cleveland Clinic Cole Eye Institute.
Edited by Charlotte E. Grayson, MD, Oct. 2003.