Age-related macular degeneration (AMD) is a progressive eye condition that affects central vision and is a leading cause of blindness in older adults. There are two forms: dry AMD, which causes gradual vision changes over many years, and wet AMD, which causes sudden, severe vision loss. AMD results from normal aging processes that damage the macula, a part of the retina. Optometrists can detect AMD through eye exams, by looking for changes in the macula and having patients view an Amsler grid. Regular eye exams are important for early detection and treatment.

1. Age Related Macular Degeneration
This is a progressive condition that can affect people as they get older. It tends to run in families.
There are different forms which have different outcomes for vision. AMD accounts for 45% of people
over 70 years of age who are registered as legally blind. With macular degeneration central vision
does become severely affected but sufferers will retain a certain level of peripheral vision.
The following figures relate to the percentage of the population suffering from diabetes.
4% of over 40s
9% of over 50s
23% of over 60s
30% of over 80s
What causes AMD?
AMD is the result of ageing processes in the eye. The part of the retina (the tissue on the inside of
the eye) responsible for seeing fine detail and colours and for making out facial features and shapes,
is the macula. The macula is affected in age-related macular degeneration. The part of the eye
suffers “wear and tear” over time and it is believed that a build up of waste material at and around
the macula is the reason for the reduction in vision that occurs in this condition.
Symptoms: There are two types of AMD, Dry & Wet
Dry AMD is the most common form of the condition and usually causes gradual changes in vision,
often little changes over many years.
Wet AMD affects a much smaller percentage of sufferers and is usually of sudden onset with
significant and obvious reduction in vision. In Wet AMD, abnormal blood vessels develop beneath
the macula and begin to leak. This leakage of fluid results in straight lines looking wavy or distorted.
In some cases of Wet AMD treatment is possible, but it is vital that referral to a retinal specialist
occurs as soon as possible.
How is AMD directed and diagnosed?
People with AMD may notice that their vision has deteriorated. Many patients do not realise that
they have a problem until their vision becomes significantly blurred. Optometrists perform a number
of tests in an examination that enable them to detect the presence of AMD in the early stages.

2. The optometrist examines the macula carefully with an instrument called an ophthalmoscope that
allows examination of the interior of the eye. Sometimes the optometrist may place a drop in the
eye to dilate the pupil to get a better view of the internal structures. Through the ophthalmoscope
the optometrist will look for changes in the structure of the macula such as accumulations of waste
material or new blood vessels.
Another test that may be used is a grid pattern known as the Amsler chart. Patients with AMD often
report that sections of the grid appear to be distorted or missing.
Optometrists will usually refer patients whom they suspect have AMD to an ophthalmologist (eye
specialist) for confirmation of the diagnosis.
What should you do to avoid AMD?
For treatment of AMD to be effective it must be diagnosed as early as possible. Regular eye
examinations are the key to early detection of retinal changes and other signs of disease. If you
notice any change in the quality of your vision, have your eyes examined immediately. Regular
examinations are particularly important for people over the age of 50 years and people whose
families have a history of eye conditions.