Macular Degeneration (AMD)
Age-Related Macular Degeneration: Facts & Treatments
What is Age-related Macular Degeneration (AMD)?
Age-Related Macular Degeneration (AMD) is one of the most common causes of poor vision in people after the age of 55. AMD is a deterioration or breakdown of the macula, which is a small area at the center of the retina in the back of the eye. It allows us to see fine details clearly and perform activities such as reading and driving.
AMD is an ocular chronic degenerative disease and causes a loss of vision in the center of the eye’s visual field, which we use for looking directly at objects. The loss of this sharp, central vision can be devastating since we use it all day long to look at pictures, read, watch television, or look at our loved ones faces. Age-related Macular Degeneration does not cause total blindness because it does not compromise our peripheral vision. However, life with poor or absent foveal vision can be extremely challenging.
Prevalence and Types of AMD
Surprisingly, many people have never heard of AMD, which is the leading cause of severe vision loss and legal blindness in people over 50 in the western world. AMD increases in prevalence the higher in age someone becomes. There are two types of AMD: dry and wet. Some people may start out with dry macular degeneration, but that doesn't mean it will remain that way. Dry macular degeneration can develop into the wet type over time.
While both the dry and wet forms of AMD cause permanent damage to the macula, dry AMD affects 9 out of 10 people who have AMD and progresses slowly. The damage dry AMD can causes may go unnoticed for years because it can be a very gradual process. People with dry AMD might notice that they now need a bright light or a magnifying glass to see as well as they used to. Sometimes, they may also notice spots in their vision that appear blurry.
While wet AMD is much less common with only 1 out of 10 people being affected by it, wet AMD is much more aggressive than dry AMD and is more serious because it can develop rapidly. Wet AMD can cause severe vision loss in as little as a couple of weeks. In the wet form of AMD, abnormal blood vessels grow in a layer beneath the retina that leak fluid and blood creating distortions in vision. A large blind spot in the center of your vision is generally you will see if you have wet AMD. When people with wet AMD look at straight lines; the lines may appear bent or wavy. For this reason, doctors often test people’s vision by asking them to look at a grid of straight lines. Those who see the lines as wavy or bent are considered as possible having wet AMD.
If you notice vision loss or any other of the symptoms listed above, see an eye doctor as soon as possible.
AMD Risk Factors
Although the specific cause is unknown, AMD seems to be directly related to the aging process. While age may be the most significant risk factor in developing AMD, other factorsthat have been identified are heredity, high blood pressure, and cardiovascular disease. Smoking, lack of exercise, exposure to sunlight, and a diet high in saturated or trans-fats are all lifestyle factors that are thought to help contribute to, or accelerate the development of AMD.
Prevention and Early Detection of AMD
Vision loss due to wet or dry macular degeneration cannot be recovered. This is the reason why early detection and intervention are extremely important in order to delay, reduce, or even prevent vision loss. Regular eye examinations are also vital in preventing AMD and receiving timely treatment if AMD is detected.
Stay alert to changes in your vision and use your Amsler grid at home on a regular basis. Contact your eye doctor immediately if any of the straight lines appear wavy or bent, any of the boxes differ in size or shape from the others, or if any of the lines are missing, blurry or discolored.
Treatments for Dry AMD
Eye Health MD offers effective new treatments for patients with both wet and dry macular degeneration. Treatments for AMD are aimed at stopping or slowing the macular damage which in turn prevents or slows the loss of vision that results from this disease. While there are no treatments found to effectively reverse dry AMD, research has shown that certain vitamin and mineral supplement formulations can dramatically slow the condition’s progress by protecting the eye from the damage caused by AMD. These supplements are sold without a prescription, but it is advised to ask your doctor before you start taking it because certain vitamins can be harmful in people who smoke.
Treatments for Wet AMD
The eventual outcome of untreated wet AMD can be severe and permanent central vision loss, with vision dropping to legal blindness or lower. Treatments for wet AMD work by destroying abnormal blood vessels in the retina, or by preventing new blood vessels from forming there. Destroying these new blood vessels via treatments are important because the abnormal vessels are the reason as to why the vision dramatically decreases over time. These treatments have been clinically proven to stop or slow the development of the condition, and some people even experience improvements in their vision. However, there is no cure for wet AMD and treatments need to be repeated.
Treatment options include: intravitreal injections (injections of medicine into the back of the eye), photodynamic therapy (PDT or “cold” laser), as well as standard laser treatment (“hot” laser).
Intravitreal Injections: Treatment for Wet AMD
Currently, there are three types of intravitreal injection medications available; Lucentis (ranibizumab), Eylea (Aflibercept), and Avastin (bevacizumab). They work in similar ways to inhibit a key effect that causes abnormal blood vessels to grow and leak. The injections help block these abnormal blood vessels, slow their leaking, and help reduce vision loss. Lucentis was originally designed for use in the eye and Avastin was originally designed to treat cancer but doctors discovered that both have similar risks and benefits to treating AMD. Insurance coverage for each medication varies and your retina specialist will help you choose which medication is most appropriate for your situation.
This treatment is performed by injecting the medicine with a very fine needle into the back of the eye. The retina specialist will clean the eye to help reduce the risk of infection and will administer an anesthetic into the eye to reduce any pain that may occur. Usually patients receive multiple intravitreal injections over the course of many months. Although not every patient benefits from intravitreal injections, a large majority of patients achieve stabilized vision, and a significant percentage may have noticeably improved vision.
This treatment involves an injection called Visudyne® (verteporfin), into the vein that “sticks to” abnormal blood vessels. This medication is activated when it is exposed to light. After the injection has been administered, the doctor will shine a special light into the eye. When the light is directed at the abnormal blood vessels in the back of the eye, the medicine will become activated and will begin destroying them. These treatments must always be repeated regularly as to not lose any vision over the course of time.
This treatment involves the retina specialist shining lasers into the eye and uses the laser to destroy the abnormal blood vessels in the retina. It is less invasive then the injection method, however the eye is still numbed during treatment. It is relatively painless but doesn't offer a cure for AMD.