What is macular degeneration?
The macula is the part of the eye responsible for central or detailed vision. It allows you to read a newspaper or a road sign while driving. “Degeneration” refers to the loss of normal function over time.
Macular degeneration is not just a result of aging. The condition results from complex hereditary and environmental influences. Still, age-related macular degeneration is the most common cause of visual loss in older Americans. This disease usually affects those 50 and older.
How does my doctor recognize macular degeneration?
Using special instruments with high-power magnification, an ophthalmologist (eye doctor) can look directly at the macula. Signs of macular degeneration may include yellow spots (called drusen), which are the accumulation of a yellow material underneath the retina, or changes in the pigment layer of the macula, which can result in increased or decreased pigment.
Drusen and pigmentary changes are seen in the early stages of macular degeneration. Many physicians refer to these early stages as age-related maculopathy and do not refer to them as macular degeneration.
Sometimes these early signs worsen. One form of late macular degeneration is called geographic atrophy. It results from thinning and severe loss of function of the retinal layers in the macula. In geographic atrophy your ophthalmologist can see the outer layers of the eyeball in greater detail than is normal.
The second late form of the disease is called exudative or wet macular generation. “Exudation” refers to the growth of new blood vessels underneath the retina which leak fluid, bleed, and cause scar tissue to build. This “wet” form of the disease is the most feared, because it can result in rapid visual loss.
Who gets macular degeneration?
Early macular degeneration is seen around the world. Late forms are more common in fair-skinned individuals. Heredity plays an important role in developing macular degeneration. However, it is not known if all patients with macular degeneration develop it due to genetics. It is known that cigarette smoking greatly increases the risk of early disease developing into more serious exudative or wet form.
Though many people believe that micronutrients and vitamins may slow the development of macular degeneration, no scientific studies have confirmed that supplements of zinc or antioxidant vitamins actually prevent the progression of macular degeneration. However, there are other reasons to consider taking antioxidant and micronutrient supplements, and there is no known harmful effect with recommended doses.
How can macular degeneration be prevented?
Because cigarette smoking increases the risk of developing wet macular degeneration, and thus vision loss, this provides another medical reason to stop smoking. High blood pressure also may play a role in increasing the occurrence of wet macular degeneration after laser surgery, so patients should work with their family doctor to regulate their blood pressure. A number of studies are investigating the possibility that zinc and antioxidant supplements will reduce or slow the progression of macular degeneration.
What can my ophthalmologist do to prevent vision loss?
In some patients, wet macular degeneration can be treated with laser surgery. Because the exudative (wet) form is caused by the growth of new blood vessels under the retina, some vision may be restored when these new vessels are destroyed with a laser. This surgery may also prevent the visual loss from progressing in some patients.
A detailed clinical examination and special eye photography usually is needed to decide if the vision loss is treatable with laser surgery. Eye photography may include highly detailed color photographs of the inside of the eye or injection of one of more dyes into a vein in the arm followed by specialized photography.
What can be done to improve vision other than laser surgery?
A low vision specialist, who may be an optometrist or an ophthalmologist, can talk to you about your specific visual needs, such as reading. Your doctor can then recommend various optical aids, ranging from magnifying lenses to closed circuit television to help you resume or continue visual tasks. Doctors are testing other types of surgery to find additional beneficial treatments for macular degeneration.