Macular degeneration of the eye begins when the central portion of the retina, the macula, begins to deteriorate. There are two forms of age-related macular degeneration (AMD). Each damages vision in its own way. The two forms are:
• Dry AMD: Dry AMD causes most cases (about 90%) of AMD. However, it only accounts for 10% of all blindness from AMD.
• Wet AMD: The situation with wet AMD is exactly the opposite: it causes only 10% of AMD but accounts for 90% of all blindness from AMD.
How is AMD diagnosed?
AMD is detected during a thorough eye examination performed by our macular degeneration doctors. The exam includes:
Who is most likely to develop AMD?
Factors that influence the risk for developing AMD include:
What happens in dry AMD?
In the dry form of macular degeneration, a yellow material begins to collect beneath the retina. This yellow material accumulates in tiny spots called drusen. At this point, patients may become aware of blurring of their central vision. Also, in dry AMD, the light sensitive cells in the macula slowly break down. With less of the macula functioning, central vision diminishes. Dry AMD often occurs in just one eye at first. Later, the other eye can be affected. Doctors have no way of knowing if or when both eyes may become involved. The cause of dry AMD is unknown.
What are the symptoms of dry AMD?
Dry AMD does not cause pain. The most common symptom of dry AMD is slightly blurred vision. The person may need more light for reading and other tasks. Also, the patient may find it hard to recognize faces until the person is very close to him or her. As dry AMD worsens, the individual may see a blurred spot in the center of his or her vision. This spot occurs because a group of cells in the macula have stopped working. Over time, the blurred spot may get bigger and denser, taking more of the patient’s central vision.
People with dry AMD in one eye often do not notice any changes in their vision. With one eye seeing clearly, they can still drive, read and see fine details. Some people may notice changes in their vision only if AMD affects both of their eyes.
What is wet age-related macular degeneration (AMD)?
In the wet form of macular degeneration, abnormal blood vessels grow under the retina. These vessels bleed, which may cause central vision to be distorted or destroyed.
As you may know, wet AMD is a chronic condition of the eye that causes central vision loss. It affects your central vision, which is the center area of what you see. In fact, most of the things we do everyday, such as drive, read, or even watch TV, require central vision. This central vision loss from wet AMD is caused by damage of the retina, otherwise known as the macula.
For some people, wet AMD progresses slowly. For others, it may progress faster. AMD is a major cause of central vision loss in Americans ages 55 or older. When you’ve lived your life being able to do the things you want when you want, central vision loss can leave you missing more than just your sight.
Macular degeneration treatment can take many forms, and numerous modalities continue to become available due to continuous research in this field. Our macular degeneration doctors perform all of the state-of-the-art treatments for macular degeneration in addition to surgery.
Lucentis™ (ranibizumab injection) is a prescription medicine for the treatment of patients with wet age-related macular degeneration (AMD). Lucentis™ has been shown to maintain or improve vision in wet AMD.
Lucentis™ is injected directly into the eye. Currently, the drug is supposed to be given every month for the rest of a patient’s life. Not all patients need such frequent wet age-related macular degeneration treatments, however.
Who is Lucentis™ for?
Like any prescription medication, Lucentis™ is not for everyone. You should not use Lucentis™ if you have an infection in or around the eye. Like other injections given into the eye, serious eye infection and detached retina have occurred with Lucentis™. Increases in eye pressure have been seen within one hour of an injection. Your eye doctor will carefully monitor your eye pressure and eye health during the week after every injection.
Although uncommon, conditions with certain blood clots (arterial thromboembolic events) may occur.
Serious side effects related to the injection procedure are rare. These include serious eye infection, detached retina and cataract. Other uncommon serious side effects include inflammation inside the eye and increased eye pressure.
The most common side effects are red eye, eye pain and small specks in vision.
Avastin™ (bevacizumab) was not initially developed to treat eye conditions. Based upon the results of clinical trials that demonstrated its safety and effectiveness, Avastin™ was approved by the Food and Drug Administration (FDA) for the treatment of metastatic colon-rectal cancer. As a condition of approval, the manufacturer produced a “label” explaining the indications, risks and benefits. The label explains that Avastin™ works by blocking a substance known as vascular endothelial growth factor, or VEGF. Blocking or inhibiting VEGF helps prevent further growth of the blood vessels that the cancer needs to continue growing.
Ophthalmologists are using Avastin™ to treat AMD and similar conditions, since research indicates that VEGF is one of the causes for the growth of the abnormal vessels that cause these conditions. Some patients treated with Avastin™ had less fluid and more normal-appearing maculas, and their vision improved. Avastin™ is also used, therefore, to treat macular edema, or swelling of the macula.
The goal of treatment is to prevent further loss of vision. Although some patients have regained vision, the medication may not restore vision that has already been lost and may not ultimately prevent further loss of vision caused by the disease. After the pupil is dilated and the eye is numbed with anesthesia, the medication is injected into the vitreous or jelly-like substance in the back chamber of the eye. Avastin™ is administered by an injection into your eye as needed at regular intervals (about every four to six weeks); your ophthalmologist will tell you how often you will receive the injection, and for how long.
You do not have to receive macular degeneration treatment for your condition, although without treatment, these diseases can lead to further vision loss and blindness, sometimes very quickly. Our macular degeneration doctors can discuss the various forms of treatment that are available. Presently there are two FDA-approved treatments for neovascular age-related macular degeneration:
Is there any other way to slow down AMD?
It has been reported that supplements of zinc and the antioxidants vitamin C, vitamin E and beta-carotene can slow the progression of wet AMD. In people with intermediate-stage disease, zinc reduced the risk of the disease progressing to the advanced stage by 11%, and the antioxidants reduced the risk by 10%. When the two were combined, the risk was reduced by 19%.
Where can I get these vitamins?
We have vitamins specifically formulated for the dry and wet forms of macular degeneration. Ask your doctor or one of the office staff for further information.
What can a person do if he or she has already lost some vision to AMD?
Normal use of the eyes will not cause further damage to vision. Even if a person has lost some sight to AMD, he or she should not be in the least afraid to use his or her eyes for reading, watching TV and other normal activities.
Low vision aids are available to help patients make the most of their remaining vision. Low vision aids are special lenses or electronic systems that make images appear larger. If a patient needs low vision aids, the doctor can often prescribe them or refer the patient to a low vision specialist.
The Role of Retina
The retina is the light-sensitive area found at the back of the eye that is critical to seeing. It can turn light or an image into electrical impulses or signals to your brain. It’s your brain that works with your retinal to decide what it is that you are looking at.
The Role of the Macula
The macula is located in the center of the retina. It is the area that lets you see color and fine detail, which is critical to performing everyday activities. The macula helps you in tasks like reading or cooking. If you are reading a book, the macula allows you to see the words on each page. If you are cooking, it will help you see that the cookies are just right or are burning.
If the macula is damaged because of wet AMD, you’ll have blurred central vision. You may also notice that straight lines seem wavy.
Monitor Your Vision Regularly with an Amsler Grid
It’s very important to monitor your vision, but it’s also important to have regular eye examinations. If you notice any changes to your vision, talk to a retina specialist right away!
What is an Amsler Grid?
The Amsler Grid is a basic test that may help determine if you have AMD. It is a grid of black lines on a white background with a dot in the middle. The grid should appear to have perfectly straight horizontal and vertical lines with a dot in the center. However, if the area around the dot appears to be wavy, it may be a sign of wet AMD. If you notice any wavy lines or blurriness at all, make an appointment with one of our retina specialists.
When doing this test, keep the following in mind:
Where is there more information about macular degeneration?
American Academy of Ophthalmology
655 Beach Street, P.O. Box 7424
San Francisco, CA 94109-7424
American Optometric Association
243 Lindbergh Boulevard
St. Louis, MO 63141
Association for Macular Diseases
210 E. 64th Street
New York, NY 10021
Foundation Fighting Blindness
Executive Plaza 1, Suite 800
11350 McCormick Road
Hunt Valley, MD 21031-1014
Macular Degeneration International
6700 North Oracle Road, Suite 121
Tuscon, AZ 85704
National Eye Institute
2020 Vision Place
Bethesda, MD 20892-3655