Condition 101 About Age-Related Macular Degeneration
What is the definition of Age-Related Macular Degeneration?
Macular degeneration, also known as age-related macular degeneration (AMD), is the deterioration of the part of the eye (macula) that allows for seeing clearly in the center of the field of vision, as well as the ability to see straight ahead, and is the leading cause of central vision loss among older individuals over the age of 50.
Macular degeneration has two types: 1) Dry macular degeneration, and 2) Wet macular degeneration.
Dry macular degeneration, also known as Non-neovascular macular degeneration, is the most common type (90%) and gradually causes significant vision loss as the macular cells deteriorate, leading to blurry vision and blank spots in the center field of vision.
Wet macular degeneration is the less common and more serious type (10%) and occurs when new blood vessels grow (choroidal neovascularization; CNV) beneath the retina that leak blood and fluid into the macula and cause scarring that leads to rapid vision loss.
Age-related macular degeneration is more common in individuals of European descent.
What are the alternative names for Age-Related Macular Degeneration?
There are several alternative names for macular degeneration, including age-related macular degeneration (AMD), age-related maculopathy, and ARMD.
What are the causes for Age-Related Macular Degeneration?
Researchers believe that the causes of macular degeneration are a combination of genetic and environmental factors. While several types of genes and genetic mutations possibly contribute to the development of the disease, aging is the main risk factor for developing the macular degeneration.
Other risk factors for developing macular degeneration include being Caucasian, having high blood pressure (hypertension), obesity, eating a diet high in fat with a high glycemic index or low in antioxidants and zinc, smoking cigarettes, having cardiovascular disease, such as high blood cholesterol levels, exposure to ultraviolet (UV) rays from sunlight, and having a family history of age-related macular degeneration.
What are the symptoms for Age-Related Macular Degeneration?
While early macular degeneration may have no symptoms, symptoms of later macular degeneration may include blurry vision and the gradual or rapid loss (depending on the type) of the ability to see straight ahead and to have fine, detailed vision; slower vision adjustment to darkness (dark adaptation) and dim light; the decreased ability to recognize friends; visual hallucinations (Charles Bonnet Syndrome); and the appearance of fluffy, yellow-white spots (drusen) on the macula of the eye.
An early symptom of wet age-related macular degeneration may include the seeing straight lines or edges that appear crooked.
What are the current treatments for Age-Related Macular Degeneration?
While there is no cure for either dry or wet age-related macular degeneration, treatment depends on the type and may help to slow progression of the disease.
Treatments for dry age-related macular degeneration focus on slowing progression of the disease and prevention of the disease in the other eye and includes vitamin regimens, such as 500 milligrams of Vitamin C; 400 International Units of Vitamin E; 15 milligrams of beta-carotene (25,000 International Units of Vitamin A) or 10 milligrams of lutein and 2 mg of zeaxanthin for smokers; 80 milligrams of zinc oxide; and 2 milligrams of copper (cupric oxide); and eating a diet high in leafy vegetables and nuts.
Treatments for wet age-related macular degeneration also focus on slowing the progression of the disease and include the vitamin regimen listed above; anti-vascular endothelial growth factor (anti-VEGF) therapy, which are drugs given by injection into the eye (intravitreal) that stop the growth of abnormal blood vessels and leakage of blood into the macula, and which may possibly help to restore lost vision; and laser and photodynamic therapy, using a light-activated drug, verteporfin (Visudyne), to seal the leaky blood vessels.
For macular degeneration that is progressing and/or threatening vision, intravitreal (in the eye) injections of the drugs, bevacizumab, aflibercept, or ranibizumab, may be administered with or without laser therapy.
In addition the above treatments, patients with age-related macular degeneration who have lost vision may need to use low-vision aids, such as optical devices, magnifying spectacles, handheld magnifiers, stand magnifiers, large type on computers and/or talking computers, large print books and newspapers, high-contrast watches, enhanced lighting, and visual rehabilitation.
Rarely, in some select patients, an implantable miniature telescope may be implanted into the eye to help improve vision and quality of life.
What are the support groups for Age-Related Macular Degeneration?
There are several online, local, national, and international support groups for macular degeneration, including the following:
American Macular Degeneration Foundation - https://www.macular.org/
Macular Society - https://www.macularsociety.org/local-support-groups
MD Support - http://www.mdsupport.org/support/
What is the outlook (prognosis) for Age-Related Macular Degeneration?
The outcomes (prognosis) for macular degeneration vary. While age-related macular degeneration is a lifelong disease, patients with early age-related macular degeneration who are treated rarely ever develop advanced vision loss and have the ability to lead fairly normal lives.
What are the possible complications for Age-Related Macular Degeneration?
Possible complications of macular degeneration include visual hallucinations (Charles Bonnet Syndrome), vision loss, and blindness.
Treatment-related complications for macular degeneration may also rarely occur, such as eye irritation or discharge or seeing spots or floaters.
When should I contact a medical professional for Age-Related Macular Degeneration?
If you experience any changes in your vision, especially those that occur suddenly and/or interfere with reading or recognizing other people, make an appointment with your doctor as soon as possible.
If you notice that straight lines or edges start to look wavy, see an ophthalmologist (eye doctor) immediately, as this symptom can indicate progressed, late stage age-related macular degeneration.
How do I prevent Age-Related Macular Degeneration?
While there is no know method to prevent macular degeneration, the risk of developing the disease can be decreased by quitting smoking, eating a diet high in green leafy vegetables, fruits, fish, and nuts, exercising regularly, and maintaining healthy blood pressure and blood cholesterol levels.
If you have a family history of age-related macular degeneration, undergoing regular eye exams is especially important to allow for early treatment, if necessary.