Facts on File Encyclopedia of Health and Medicine

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ARMD. Some research studies demonstrate the
rate of degeneration slows with increased con-
sumption of the antioxidants lutein and zeaxan-
thin, and vitamins A, C, and E. For wet ARMD the
laser treatments photocoagulation and photody-
namic therapy are sometimes effective in sealing
bleeding blood vessels and thwarting their growth,
though they cannot permanently halt the neovas-
cularization or restore vision already lost. Photo-
coagulation uses a hot laser to cauterize the blood
vessels but also destroys cells in the vicinity of the
targeted blood vessels. With photodynamic ther-
apy, the ophthalmologist injects a photosensitive
DRUGinto the person’s veins, then uses a cool laser
to target blood vessels in the retina when the drug
reaches them. The light of the laser is not intense
enough to burn the tissue though activates the
drug, which then destroys the blood vessels.


Outlook and Lifestyle Modifications

For most people who have ARMD vision declines
slowly and may affect only one eye for a long time
before affecting the other eye as well. Because the
loss affects the center of the field of vision, vision
loss is not complete though affects activities that
require detailed focus, such as reading and driv-
ing, and typically reaches the level of legal blind-
ness. Numerous community and health-care
resources can assist with adaptive methods to
accommodate diminishing vision. Even with wet
ARMD, which progresses more rapidly and more
severely than dry ARMD, some vision remains.


Causes and Preventive Measures

Researchers do not know what causes ARMD,
though it appears to have a hereditary component
in that it runs in families. There are few treat-
ments, and there is no cure, though there is evi-
dence that antioxidants slow the rate of
deterioration and the loss of vision. Vision loss is
permanent. As yet there are no known measures
to prevent ARMD. It appears that ARMD is more
common in people who:



  • smoke cigarettes

  • have blue or green eyes

  • experience extensive exposure to ultraviolet
    rays, as in sunlight exposure

    • have CARDIOVASCULAR DISEASE (CVD) such as
      HYPERTENSION(high blood pressure), ATHEROSCLE-
      ROSIS, or CORONARY ARTERY DISEASE(CAD)




People who have more than one risk factor,
especially when one of the risk factors is family
history, should frequently and regularly monitor
their vision using the Amsler grid. Early diagnosis
is particularly important with wet ARMD, for
which limited treatment options exist. ARMD
develops in people over age 50. An ophthalmolo-
gist should evaluate changes that alter the field of
vision, especially those that take the form of dis-
tortions or “missing pieces.” Regular ophthalmic
examinations are important to detect ARMD as
well as other conditions that affect the eye and
vision with advancing age.
See also AGING, VISION AND EYE CHANGES THAT
OCCUR WITH; HEMORRHAGE; OPHTHALMIC EXAMINATION;
RETINAL DETACHMENT; VISION HEALTH.

aging, vision and eye changes that occur with
The structures of the EYEand the processes of
vision begin to undergo changes in the late fourth
or early fifth decade of life. By age 65, 50 percent
of people have vision impairments. By age 80,
more than 90 percent of people have vision
impairments. Treatment can mitigate some of
these changes, such as PRESBYOPIAand CATARACT.
Some conditions that affect the eye and vision
develop secondary to other health conditions that
are more prevalent in older people, such as DIA-
BETES, HYPERTENSION, and KIDNEY disease, all of
which can cause RETINOPATHY. Much loss of vision
related to aging is progressive and permanent,
interfering with activities such as driving, reading
and other close work, and seeing at night. How-
ever, most people retain the ability to see well
enough to function in everyday activities.
Adaptations to accommodate the changes of
the eye and vision with aging are numerous and
can help maintain a desirable QUALITY OF LIFEfor
many people. CORRECTIVE LENSESor reading glasses
are effective for presbyopia. Surgery can improve
vision impairments such as cataract (CATARACT
EXTRACTION AND LENS REPLACEMENT), corneal damage
(corneal reshaping or CORNEAL TRANSPLANTATION),
and PTOSISand ECTROPION(BLEPHAROPLASTY). Magni-

aging, vision and eye changes that occur with 71
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