Age-related macular degeneraton (AMD)
What is age-related macular disease (senile macular degeneration)?
Age-related macular disease is one of the most important causes of irreversible vision loss in people over 60 years of age. The disease affects the macula, a yellow spot located at the rear of the eye, which is the center of the visual field. The macula is responsible for the sharpness and colourfulness of our vision. Damage occurring in this region, adversely affects vision, vision decreases, initially straight lines appear curved or broken, and then a black spot appears in the centre of the visual field. The patient’s exact centre of vision is blurred but the surrounding areas are visable. As macular degeneration progresses, quality of life is reduced. Daily activities such as reading a book or newspaper, driving a car or watching television become difficult. Macular degeneration does not leave patients completely blind, but vision can very significantly reduced. If the disease is diagnosed and treated early, current levels of sight can be maintained and the further loss of sight can be prevented. This disease is more common in Caucasians of advanced age. Other factors which increase risk are smoking, hypertension, high blood lipids, high exposure to sunlight and a family history of this illness.
There are two forms of this disease, “dry” and “wet” type. The “dry” form is more common and accounts for the vast majority of patients (approximately 90%). This type progresses slowly. Only 10% of cases are “wet” form but, due to it’s swift progression, it is “wet” type that is largely responsible for the irreversible loss of central vision. “Dry” form can also sometimes develop into “wet” form.
The most important issue with regard to AMD is early diagnosis and early treatment. Because the actual goal of treatment is the protection of existing vision. Loss of vision is often irreversible, but the progression can be stopped. Sometimes treatment can improve vision, but this is very rare.
The most important early diagnostic tests are fundus fluorescein angiography (FFA), where coloured liquid is injected into the arm and images are taken of the rear section of the eye, and optical coherence tomography (OCT), which is used to examine and assess the makula area of the eye.
Orally administered medication for the treatment of “dry” form AMD :
For “dry” types of macular degeneration pills containing anti-oxidants, vitamin A, C and E, lutein, and zinc may help as protective treatment.
Drug injection for the treatment of “wet” form AMD :
“Wet” form AMD can be treated with injections directly into the vitreous humor of the eye. This is a quick and simple procedure and causes no pain to the patient. It sends a type of protein called an anti-VEGF antibody into the eye. This drug can cause regression of the abnormal blood vessels that develop in the yellow spot area behind the eye, this stops the deterioration of vision and in some cases can even improve vision.
AMD Amsler grid test :
This test allows patients to test the functions of their yellow spot area by themselves. Using this test it is possible to detect the early signs of “wet” macular disease.
- Put on your reading glasses.
- Hold the card steadily, about 30 – 40 cm away from your face.
- Cover one eye with your hand and focus on the black dot using the open eye. Note whether you can see each of the 4 corners of the large square in the diagram.
- Test the other eye in the same way.
- If the lines are wavy, broken, blurred or you cannot see the corners, this could be a sign of AMD