The macula is the most central part of
the retina, the film like structure of the eye that transmits
your vision from the eye to the brain. Macular degeneration
is a multifactorial genetic process in which the macula of
the retina degenerates and atrophies. This is the leading
cause of functional blindness in America in people over the
age of 60 years. Thankfully this is a slow process that can
take years to develop. It occurs in two forms, the initial
“dry” form and the late “wet” form.
In the dry form, waste material form the rods and cones in
the retina pile up under the retina and accumulate. These
collections, called drusen, eventually lead to retinal break
down and atrophy in the areas overlying the drusen. Vitamin
therapy, along with amsler
grid testing, is recommended in most patients
with early ARMD to prevent vision loss. Dry age related macular degeneration accounts
for 90% of patients.
The wet form only occurs in 10% of patients with macular
degeneration, but is much more devastating to the vision.
In areas where the retina has degenerated, the underlying
blood vessels that feed the outer retina grow up in these
injured areas of retina. Biochemical signals are responsible
for this growth. In the past, laser treatments alone were
used destroy these vessels. Today a combination of laser treatments,
photodynamic therapy and most recently, eye injections with
anti-growth factor type medicines like Lucentis, Avastin and
Macugen, slow down or halt the damage from these leaking and
bleeding vessels.
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