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Macular
Degeneration (AMD)
Age-related Macular
Degeneration, or AMD, is
the leading cause
of vision loss in the western
world, and typically affects
people over 60 years of age.
The specialists at Auckland's
Eye Institute are
leaders
in ophthalmology,
AMD diagnosis and Macular
Degeneration
treatments.
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What is the macular?
Our eyes are like a camera with a lens
system at the front of the eye, and
the retina, like a photographic film,
lining the inside wall of the back
of the eye. Light passes through
the cornea, pupil and lens and is
focused on the light sensitive retina
to form an image. Messages are sent
via the optic nerve to the brain
for processing.
 The macula is the central part of
the retina. It is a small, specialized
area in the middle of the retina
and is responsible for our ability
to
see fine detail. This central vision
is the vision we use for reading,
driving, recognising faces, threading
needles
and other fine detailed work. The
remaining part of the retina is responsible
for our side vision, also known as
peripheral vision.
This is our mobility vision, allowing
us to get about and to maintain our independence.
What is AMD?
With AMD, there is damage or breakdown
of the macula, leading to loss of central
vision. The eye still sees objects to
the side since peripheral vision is not
affected. For this reason macular degeneration
does not result in total blindness. The
most common form of the disease is known
as Dry AMD. This form
occurs in approximately 80 to 90% of
people with AMD. In Dry
AMD the vision loss is usually very gradual
and is seldom severe. Areas of the central
retina gradually become thin and stop
working. Some people notice blank areas
in their vision. Vitamin supplementation,
diet modification and stopping smoking
can all decrease the rate at which this
gets worse, and the eyesight may also
be helped somewhat with the use of special
low-vision magnifying lenses.
Some people
develop a more aggressive form of the
disease called Wet AMD that
can lead to rapid and severe vision loss.
This
occurs in only 10 to 15% of people with
macular degeneration. In Wet AMD, abnormal
blood vessels grow under the macula and
eventually leak fluid, bleed or lift
up the retina. When this happens central
vision is reduced and often distorted.
The longer these abnormal new vessels
continue to leak, bleed and grow, the
more central vision will be lost.
 Left
untreated, these fragile vessels will
cause scarring and irreversible
loss of the detailed central vision.
Sometimes only one eye loses vision while
the other eye continues to see well for
many
years. If both eyes are affected however,
reading and close-up work may become
extremely difficult. It does not cause
blindness and since the sidevision remains,
people can usually take care of themselves
quite well.
What are the symptoms of Macular
Degeneration?
Most patients with AMD will notice difficulty
in reading as words become blurred or
crowded. There may be a black or grey
spot in your central vision. A frequent
and important early symptom of Wet AMD
is distortion when straight lines appear
bent or wavy. You may become aware of
this when looking at a page of small
print or looking at a window frame or
telephone pole with your affected eye.
These changes in eyesight are important
symptoms and if they occur you should
contact your ophthalmologist promptly.
Do not assume you simply need a new pair
of glasses and wait for an appointment
in the future.
How is AMD diagnosed?
 Many
people do not realize they have macular
problems until blurred vision
becomes obvious. An eye specialist can
examine the macula and identify early
changes. If Wet AMD is suspected, special
tests called optical coherence tomography
(OCT) and fluorescein angiogram are
usually required. OCT is a no-touch method
of scanning the macula to look for fluid
leaks, the first sign of Wet AMD. It
only takes a minute to do, and no
needles or touching of the eye are required.
Fluorescein angiography is used to locate
exactly where the leaking blood vessels
are. In this test, dye is injected into
a vein in the arm. The dye travels through
the body, and with a special camera a
series of photographs are taken as the
dye passes through the retina, putting
together a map of the problem which can
be used by the doctor during treatment.
What is the treatment for AMD?
With any kind of AMD, various measures
have been shown to decrease the risk
of the disease getting worse. These include:
- Vitamin Supplementation
A large American study, the Age-Related
Eye. Diseases Study (AREDS) found that
using certain combinations of vitamins
could reduce the chance of AMD getting
worse by about one quarter.
Eye Institute is able to supply “Ocuvite
Preservision” and “Ocuvite
Lutein”
Ocuvite Preservision
Gel Tabs
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$48
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Ocuvite Lutein
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$45 |
- Stopping smoking
Smokers are at higher risk of AMD,
and of Wet AMD in particular.
It is therefore very important
to stop
smoking at the earliest sign
of this condition.
- Dietary changes
Various foods seem to protect against
the development of Wet AMD, including
nuts and fish oils.
With Wet AMD, several different treatments
are possible:
- Avastin and Lucentis Injections
These drugs are both very new but
at present appear to be the best
treatment for Wet AMD. They are
injected into the eye, and may
need to be
repeated several times over the
course of
several months, but they have been
shown to improve vision in people
with Wet AMD, so long as scarring
has not started to take place.
No other treatment seems to improve
vision;
other treatments can only decrease
the rate at which things get worse.
- Thermal
Laser Therapy (Photocoagulation)
In this procedure, the heat
from a laser light is used
to cauterize
the abnormal leaky blood vessels.
This treatment also damages
overlying normal
retina.
- Photodynamic Therapy (PDT)
PDT uses a light-activated drug
(Visudyne) and a special
non-thermal laser to selectively
destroy abnormal
blood vessels while preserving
surrounding normal healthy tissue.
Amsler Grid Eye Exam
Directions:
- Wear the glasses or contacts
you normally wear for reading.
- View the
grid at reading distance (approx
30cm) in a well-lit room.
- Cover
one eye with your hand and focus
on the centre dot with your uncovered
eye. Repeat with the other eye.
- If you
see wavy, broken or distorted
lines, or blurred or missing areas
of vision you may be displaying
symptoms
of AMD and should contact your
eye care provider immediately.
THE COMPLETE EYE-CARE SPECIALISTS
The specialists at the Eye Institute
are acknowledged leaders in ophthalmology,
including refractive surgery, laser,
cataract and glaucoma surgery. We
also offer expertise in retina, squint,
eyelid surgery, eye infections and
inflammation, and neuro-ophthalmology.
Our
focus on excellence prompted us to
develop New Zealand’s first
purpose-built day-stay hospital.
This enables us to enhance our quality
of care while keeping costs amongst
the lowest in the eye care field.
As
an added benefit we also offer a
special finance plan to help you
with your budgeting, go to:www.novamedical.co.nz
We provide free video tapes and brochures
answering common questions about laser
vision correction, cataract surgery,
retinal surgery, glaucoma, macular
degeneration, pterygium, dry eyes and
strabismus (squint). Please don’t
hesitate to ask for more information
To make
an appointment, or to find out
more information, fill out our enquiry
form, or contact Eye
Institute's friendly team on free
phone 0800 393 527.
Affiliated provider benefit to Cataract Patients
- no need for prior approval
- no money up front for surgery
- Southern Cross pays us directly
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