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Age-Related Macular Degeneration Fact Book
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This pamphlet is designed to help people with age-related macular
degeneration and their families better understand the disease. It
describes the causes, symptoms, diagnosis, and treatment of
age-related macular degeneration.
Age-related macular degeneration (AMD) is a disease that affects
your central vision. It is a common cause of vision loss among
people over age of 60. Because only the center of your vision is
usually affected, people rarely go blind from the disease. However,
AMD can sometimes make it difficult to read, drive, or perform other
daily activities that require fine, central vision.
The macula is in the center of the retina, the
light-sensitive layer of tissue at the back of the eye. As you read,
light is focused onto your macula. There, millions of cells change
the light into nerve signals that tell the brain what you are
seeing. This is called your central vision. With it, you are
able to read, drive, and perform other activities that require fine,
sharp, straight-ahead vision.
AMD occurs in two forms:
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Although AMD can occur during middle age, the risk increases as a
person gets older. Results of a large study show that people in
their 50s have about a two percent chance of getting AMD. This risk
rises to nearly 30 percent in those over age 75. Besides age, other
AMD risk factors include:
Gender--Women may be at greater risk than men, according
to some studies.
Smoking--Smoking may increase the risk of AMD.
Family History--People with a family history of AMD may be
at higher risk of getting the disease.
Cholesterol--People with elevated levels of blood
cholesterol may be at higher risk for wet AMD.
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Neither dry nor wet AMD causes any pain. The most common symptom
of dry AMD is slightly blurred vision. You may need more light for
reading and other tasks. Also, you may find it hard to recognize
faces until you are very close to them.
As dry AMD gets worse, you may see a blurred spot in the center
of your vision. This spot occurs because a group of cells in the
macula have stopped working properly. Over time, the blurred spot
may get bigger and darker, taking more of your central vision.
People with dry AMD in one eye often do not notice any changes in
their vision. With one eye seeing clearly, they can still drive,
read, and see fine details. Some people may notice changes in their
vision only if AMD affects both of their eyes.
An early symptom of wet AMD is that straight lines appear wavy.
This happens because the newly formed blood vessels leak fluid under
the macula. The fluid raises the macula from its normal place at the
back of the eye and distorts your vision. Another sign that you may
have wet AMD is rapid loss of your central vision. This is different
from dry AMD in which loss of central vision occurs slowly. As in
dry AMD, you may also notice a blind spot.
Normal vision. 
The same scene as it might be
viewed by a person with
AMD. If you notice any of these changes in your vision, contact your
eye care professional at once for an eye exam.
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Eye care professionals detect AMD during an eye examination that
includes:
Visual acuity test: This eye chart test measures how well
you see at various distances.
Pupil dilation: This examination enables your eye care
professional to see more of the retina and look for signs of AMD. To
do this, drops are placed into the eye to dilate (widen) the pupil.
After the examination, your vision may remain blurred for several
hours.
One of the most common early signs of AMD is the presence of
drusen. Drusen are tiny yellow deposits in the retina. Your
eye care professional can see them during an eye examination. The
presence of drusen alone does not indicate a disease, but it might
mean that the eye is at risk for developing more severe AMD.
While conducting the examination, your eye care professional may
ask you to look at an Amsler grid. This grid is a pattern
that resembles a checkerboard. You will be asked to cover one eye
and stare at a black dot in the center of the grid. While staring at
the dot, you may notice that the straight lines in the pattern
appear wavy to you. You may notice that some of the lines are
missing. These may be signs of wet AMD (See Amsler Grid
below.)
If your eye care professional suspects you have wet AMD, you may
need to have a test called fluorescein angiography. In this
test, a special dye is injected into a vein in your arm. Pictures
are then taken as the dye passes through the blood vessels in the
retina. The photos help your eye care professional evaluate leaking
blood vessels to determine whether they can be treated.
On the left is what an Amsler grid normally looks like, and the
illustration on the right is how it might look to someone with AMD.
These grids are reduced in size; ask your doctor for a full-size
grid to use at home.
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Dry AMD currently cannot be treated. But this does not mean that
you will lose your sight. Fortunately, dry AMD develops very slowly.
You may lose some of your central vision over the years. However,
most people are able to lead normal, active lives--especially if AMD
affects only one eye.
Some cases of wet AMD can be treated with laser surgery. The
treatment involves aiming a high energy beam of light directly onto
the leaking blood vessels. Laser treatment is more effective if the
leaky blood vessels have developed away from the fovea--the
central part of the macula. But even if the blood vessels are
growing right behind the fovea, the treatment can be of some value
in stopping further vision loss.
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Laser surgery is performed in your eye care professional's office
or eye clinic. Before the surgery, he or she will: (1) dilate your
pupil and (2) apply drops to numb the eye. In some cases, he or she
also may numb the area behind the eye to prevent any discomfort.
The lights in the office will be dim. As you sit facing the laser
machine, your eye care professional will hold a special lens to your
eye. You may see flashes of light.
You can leave the office once the treatment is done, but you will
need someone to drive you home. Because your pupils will stay
dilated for a few hours, you also should bring a pair of
sunglasses.
For the rest of the day, your vision may be a little blurry. Your
eye may also hurt a bit. This is easily controlled with drugs that
your eye care professional can suggest.
You will need to make frequent follow-up visits. During each
exam, you may have fluorescein angiography to make sure that the
blood vessels are not still leaking, or that new blood vessels have
not developed. If the vessels continue to leak, you might need some
more laser surgery. It is important to realize that laser surgery is
not a cure for AMD. It is only a treatment to help stop further
vision loss. The risk of new blood vessels growing back after laser
treatment is relatively high.
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Dry AMD. If you have dry AMD, you should have your eyes
examined through dilated pupils at least once a year. This will
allow your eye care professional to monitor your condition and
check for other eye diseases as well.
You should also obtain an Amsler grid from an eye care
professional to use at home. This will provide you with a quick
and inexpensive test to evaluate your vision each day for signs of
wet AMD. It works best for people who still have good central
vision. You should check each eye separately--cover one eye and
look at the grid, then cover your other eye and look at the grid.
You also may want to check your vision by reading the newspaper,
watching television, and just looking at people's faces. If you
detect any changes, you should have an eye exam.
Wet AMD. If you have wet AMD, it is important not to
delay laser surgery if your eye care professional advises you to
have it. After surgery, you will need to have frequent eye
examinations to detect any recurrence of leaking blood vessels.
Studies show that people who smoke have a greater risk of
recurrence than those who don't.
In addition, you should continue to check your vision (at home
With the Amsler grid or other methods) as described under dry AMD
and schedule an eye exam immediately if you detect any
changes.
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Normal use of your eyes will not cause further damage to your
vision. Even if you have lost sight to AMD, you should not be afraid
to use your eyes for reading, watching TV, and other usual
activities.
Low vision aids are available to help you make the most of your
remaining vision. Low vision aids are special lenses or electronic
systems that make images appear larger. If you need low vision aids,
your eye care professional can often prescribe them or refer you to
a low vision specialist. In addition, groups and agencies that offer
information about counseling, training, and other special services
are available. You may also want to contact a nearby school of
medicine or optometry as well as a local agency devoted to helping
the visually impaired.
Keeping on top of Your Condition
Keeping in tune with your disease or condition not only makes treatment less intimidating but also increases its chance of success, and has been shown to lower a patients risk of complications. As well, as an informed patient, you are better able to discuss your condition and treatment options with your physician.
A new service available to patients provides a convenient means of staying informed, and ensures that the information is both reliable and accurate. If you wish to find out more about HealthNewsflash's innovative service, take the tour.
For more information about low vision programs, contact:
American Foundation for the Blind
11 Penn Plaza, Suite
300
New York, NY 10001
1-800-232-5463
212-502-7600
afbinfo@afb.org
http://www.afb.org
Council of Citizens with Low Vision
International
1-800-733-2258
Lighthouse International
111 E. 59th Street
New
York, NY 10022
1-800-829-0500
212-821-9200
http://www.lighthouse.org
National Federation of the Blind
1800 Johnson Street
Baltimore, MD 21230
410-659-9314
http://www.nfb.org
For more information about AMD, contact:
AMD Alliance International
1314 Bedford Avenue, Suite
113
Baltimore, Maryland
21208
1-877-263-7171
http://www.amdalliance.org/
American Academy of Ophthalmology
655 Beach Street,
P.O. Box 7424
San Francisco, CA 94109-7424
415-561-8500
http://www.aao.org
American Optometric Association
243 Lindbergh
Boulevard
St. Louis, MO 63141
314-991-4100
http://www.aoanet.org
Association for Macular Diseases
210 E. 64th Street
New York, NY 10021
212-605-3719
(The) Foundation Fighting Blindness
Executive Plaza 1,
Suite 800
11350 McCormick Road
Hunt Valley, MD 21031-1014
1-800-683-5555
410-785-1414
http://www.blindness.org
Macular Degeneration International
6700 North Oracle
Road, Suite 121
Tucson, AZ 85704
1-800-393-7634
520-797-2525
Macular Degeneration Partnership
8733 Beverly
Boulevard, Suite 201
Los Angeles, CA 90048
(310)
423-6455
http://www.macd.net
National Eye Institute
2020 Vision Place
Bethesda,
MD 20892-3655
301-496-5248
http://www.nei.nih.gov
Prevent Blindness America
500 East Remington Road
Schamburg, IL 60173
1-800-331-2020
847-843-2020
http://www.preventblindness.org
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