Macular Degeneration
(Age-Related Type)
What is age-related macular degeneration?
Age-related macular degeneration (AMD) is a disease associated with aging
that gradually destroys sharp, central vision. Central vision is needed for
seeing objects clearly and for common daily tasks such as reading and driving.
AMD affects the macula, the part of the eye that allows you to see fine
detail. AMD causes no pain.
In some cases, AMD advances so slowly that people notice little change in
their vision. In others, the disease progresses faster and may lead to a loss of
vision in both eyes. AMD is a leading cause of vision loss in Americans 60 years
of age and older.
AMD occurs in two forms: wet and dry.
Where is the macula?
The macula is located in the center of the retina, the light-sensitive tissue at the back of the eye. The retina instantly converts light, or an image, into electrical impulses. The retina then sends these impulses, or nerve signals, to the brain.
What is wet AMD?
Wet AMD occurs when abnormal blood vessels behind the retina start to grow
under the macula. These new blood vessels tend to be very fragile and often leak
blood and fluid. The blood and fluid raise the macula from its normal place at
the back of the eye. Damage to the macula occurs rapidly.
With wet AMD, loss of central vision can occur quickly. Wet AMD is also known
as advanced AMD. It does not have stages like dry AMD.
An early symptom of wet AMD is that straight lines appear wavy. If you notice
this condition or other changes to your vision, contact your eye care
professional at once. You need a comprehensive dilated eye exam.
What is dry AMD?
In dry AMD, the light sensitive cells in the macula slowly
break down. With less of the macula functioning, central
vision diminishes. Dry AMD often occurs
in just one eye at first. Later, the other eye can be affected.
Doctors have no way of knowing if or when both eyes may become
involved. The cause of dry AMD is unknown.
