Patient information: Age-related macular degeneration
What is the macula? The
retina lines the inside of the back of the eye. It
functions a bit like the film in the back of a camera, in that it
absorbs light to form an image of the outside world.
The most important part of the retina is the macula - this is the part
of the retina that the light is focussed on. It gives
the central vision that is important for fine visual tasks such as
reading and driving.
What is age-related macular degeneration (AMD)? This
is commonly divided into two types: wet AMD and dry AMD. Wet AMD occurs
when new blood vessels grow into the macula and then leak fluid and
blood. Dry AMD occurs when the substance of the macula degenerates
(atrophies). There are early forms of AMD that have no new
or atrophy of the macula. However, with time they do sometimes
progress to more advanced types of AMD.
What are the symptoms of AMD? Mild AMD may have no symptoms at
all, whereas advanced AMD can have a severe impact on vision.
People with AMD seldom go completely blind, but loss of central
vision may make fine visual tasks like reading and driving more
difficult, or sometimes impossible. Rapid changes in
vision, particularly blurred or distorted vision, should prompt
patients to visit an eye doctor urgently, as this may mean they have
wet AMD and this is best treated promptly.
How is AMD treated? There
is unfortunately little that can be done to treat dry AMD in the way of
drugs or surgery, although modified glasses and optical devices
help, and surgical trials are underway to establish if intraocular
telescopes may be useful for some patients. Social support and
practical aids around the house are
also a great help for some people. There are by contrast many
exciting new medical treatments for wet AMD including new types of
laser, and drugs that are injected into the eye. The new drugs
include Avastin, Lucentis, and Macugen. NHS funded Lucentis is now
available to many patients with wet AMD, if they meet the NICE criteria
for treatment. This will depend on their vision, how long the disease
has been present, and how much damage there is from AMD. There are
other types of laser treatment available
on the NHS,
some that involve the combination of laser and an injection given into
a vein in the arm (photodynamic therapy or PDT). These are only
available in the NHS in a few specialised treatment centres such
King's College Hospital. Specific
nutritional supplements (vitamins and mineral tablets) may also be
suitable for some patients and can be purchased over the counter from
pharmacies, however talk to an eye doctor about which
supplements are best suited to your condition as some are
inappropriate, or potentially harmful.
New treatments for AMD? There
are many new treatment for AMD under evaluation. For more information on the the MERLOT study of epimacular brachytherapy, and other new treatments click here.
Any further questions? There
is a wealth of information available on the internet, but it is of
variable quality. One of the best information sheets is available
free from the Royal College of Ophthalmologists (click here to view). This also provides a list of useful contact numbers.