What
is Age-Related Macular Degeneration (AMD)?
 AMD
is a common eye disease associated with aging that can gradually
destroy the sharp, central vision that is necessary for reading,
driving, and recognizing faces. In some people, AMD advances
so slowly that it has little effect on their vision as they
age. But in others, the disease progresses faster and may
lead to a loss of vision in one or both eyes resulting in
"legal" blindness. More than 13 million people in
the United States have AMD, which is the leading cause of
severe vision loss (legal blindness) in the western world.
There
are two forms of AMD:
-
Dry
AMD - accounts for 90 percent of all cases. Studies
suggest that the area at the back of the eye (called the
retina) becomes diseased, leading to a gradual loss of
central vision.
-
Wet
AMD - Although only 10 percent of all people
with AMD have the wet form, it accounts for 90 percent
of all severe vision loss from the disease. As dry AMD
worsens, new blood vessels may begin to grow and cause
"wet" AMD. Because these new blood vessels tend
to be very fragile, they often will leak blood and fluid
which can cause the loss of central vision in a short
period of time.
What
Causes AMD?
The
greatest risk factor is age. People over the age of 60 are
clearly at greater risk than other age groups and the risk
increases with age. Women, Caucasians, lightly-pigmented people
(blond hair, fair skin, blue-eyed) and those who have a family
history of the disease also are more likely to develop AMD.
Other risk factors may include diet, heart disease, sun exposure
and smoking. However, the exact cause is still poorly understood.
What
are the Symptoms of AMD?
How
AMD can distort your vision |
 |
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 worsens, you may see a fuzzy, blurred
spot in the center of your vision. Over time, the blurred
spot may get bigger and darker, reducing more of your
central vision. Early symptoms of wet AMD can include
distortion of straight lines and loss of your central
vision. These symptoms can develop suddenly, such as
overnight. |
What
You Can Do to Protect Your Vision
If
you have dry AMD, you should have a dilated eye examination
by your retina doctor at least once each year. In addition,
recent research shows that taking certain vitamins containing
high levels of vitamin C, vitamin E, beta-carotene, and zinc
can slow the progress of the dry type of the disease if you
are at high risk for developing advanced stages of AMD. Consult
your physician before starting or changing any vitamin or
supplement regime.
 If
you have wet AMD, it is important not to delay evaluations
and treatment if your retina specialist has advised you to
have it. After treatment, you will need to have frequent eye
examinations to detect any recurrence of leaking blood vessels.
People
with wet and dry AMD also should monitor their own eyesight
at home each day by checking the Amsler
grid given to you by Retina Consultants of Southwest Florida®
(also available on our web site). You should notify the office
immediately if you detect any changes on the Amsler grid card
or in your vision.
Making
the Most of Your Remaining Vision
Early
detection and treatment may reduce the loss of vision from
macular degeneration. However, if some loss of vision should
occur, it doesn’t have to rob you of life’s simplest
pleasures if you learn how to use your remaining eyesight
to see your best. Low vision aids, special lenses, or electronic
systems and training can maximize your ability to read and
perform other activities. The
Low Vision Rehabilitation Center of Retina Consultants of
Southwest Florida can give you more information about
the training and devices available.
What
are the Treatment Options?
Unfortunately,
there is no cure for either the wet or dry forms of AMD.
For
Dry AMD, there are no treatments for this condition however,
there are clinical trials underway testing some new treatments.
Even though there isn’t a treatment available right
now, that doesn’t mean you will lose your sight. Fortunately,
dry AMD develops very slowly. Most people with dry AMD are
able to lead normal, active lives.
For
Wet AMD, there are three main treatment options
- Medication
–These are drugs, usually injected into the
eye, to block abnormal blood vessels from growing and leaking
blood and fluid. This leakage or bleeding causes loss of
vision. In some cases, patients have reported improvements
in their vision.
- Thermal
Laser Treatment – This treatment involves
aiming a precise laser light beam onto the new blood vessels
to destroy them. The major value of the treatment is that
it may prevent further vision loss.
- Photodynamic
Therapy (PDT) – This treatment involves injecting
a photo-sensitive drug into the arm, which travels to the
abnormal blood vessels. The drug then is activated and seals
the abnormal blood vessels. This therapy may preserve and,
in some cases, improve vision.
Each
of these procedures is done in the Retina Consultants office
and lasts a short time. Although a person may go home the
same day, he or she will need to return for follow-up exams
and/or treatments.
How
is AMD Detected?
 Your
eye doctor may suspect AMD if you are over age 60 and have
had recent changes in your central vision. To look for signs
of the disease, he or she will use eye drops to dilate, or
enlarge, your pupils. Dilating the pupils allows your eye
doctor to view the back of the eye better. You also may be
asked to view an Amsler grid, a pattern that looks like a
checkerboard. Early changes of AMD may cause the grid to appear
distorted, or have blank areas.
If
AMD is suspected, you may need testing, including a fluorescein
angiography. In this test, a diagnostic drug is injected into
a vein in your arm. As the drug passes through the blood vessels
in the retina, pictures are taken that help your eye doctor
determine if treatment is needed.
|
: Macular
Degeneration
