Macular Degeneration (AMD)
Macular degeneration is a progressive eye condition that affects as many as 10 million Americans. Macular degeneration ― sometimes called age-related macular degeneration, or AMD ― typically occurs in people over 60 and affects the macula of the eye, where our sharpest central vision occurs.
Macular degeneration rarely results in complete blindness; typically, it causes dim images or black holes at the center of vision, leaving only peripheral vision intact.
To schedule an eye exam in Rockville, Damascus, or Washington, DC to test for macular degeneration, call (301) 896-0890. You can also schedule an appointment online.
Types of Macular Degeneration
There are two forms of macular degeneration: dry AMD and wet AMD. 80% of people diagnosed with AMD have dry AMD.
Dry macular degeneration typically begins with thinning of the retina. Tiny yellow deposits, called drusen, form at the retina base. Patients typically have slow progressive vision loss.
About 20% of patients experience a progression to wet AMD, where retinal thinning and degeneration are severe enough to cause fragile, abnormal blood vessels to form and leak, causing more rapid and significant vision loss.
Signs and Symptoms of Macular Degeneration
Macular degeneration affects the area of the retina called the macula, the part of the eye responsible for central vision. A person with this condition has difficulty seeing detailed objects such as small print, faces, or street signs. The affected areas of the macula often cause scotomas, or small central areas of vision loss.
These areas may cause objects to appear faded, disappear, or look distorted. Straight lines may look wavy. Peripheral vision is not affected and macular degeneration does not cause total blindness.
Diagnosing Macular Degeneration
Routine and yearly dilated ocular examinations are important for early management of macular degeneration. During your examination, which is done by the best macular degeneration doctors, imaging scans of the retina called optical coherence tomography (OCT) are performed, providing detailed imaging of the retina and macula.
In addition, a dye test called a fluorescein angiography may be performed. A yellow dye (called fluorescein) is injected into your vein. This dye travels through the body and into the eyes. A special camera is used to highlight abnormal new vascular growth or leakage to help identify wet AMD.
Macular Degeneration Causes and Risk Factors
While the exact cause of age-related macular degeneration (ARMD) is unknown, risk factors include:
- Age. The risk of AMD at age 50 is 2%. That rate jumps to 37% by age 75.
- Family history. Individuals with an immediate family member who has AMD are 300% more likely to experience the condition.
- Genetics. There is a strong association between development of AMD and presence of variant genes including complement factor H (CFH) and complement factor B.
- Smoking. Smokers are 5-8 times more likely to develop AMD than nonsmokers.
- Race. Caucasians and patients with light-colored skin and eyes are more likely to develop AMD than darker-pigmented patients.
- Obesity. High blood pressure and high cholesterol increase the risk of AMD.
- UV exposure. Sunglasses with 100% UV protection can reduce your risk of AMD.
- Diet. Diets high in saturated fats (i.e. meat, butter, cheese) and low in Vitamin C, Vitamin E, and lutein increase one’s risk factor for AMD.
Treating Macular Degeneration
Many patients with either type of macular degeneration can benefit from low vision rehabilitation. Prescription optical devices can help you use your remaining vision more effectively.
Dry AMD Treatments
There is no treatment for dry AMD currently. Steps you can take to slow the progression of dry AMD include:
- Daily eye vitamin intake (called AREDS Eye Vitamins)
- Wearing sunglasses with 100% UV protection
- Eating a Mediterranean diet
- Daily intake of green leafy vegetables
- Daily exercise
Studies funded by the National Institutes of Health indicate patients with intermediate and advanced dry AMD can reduce their risk of vision loss by at least 25% by maintaining high levels of antioxidants and zinc. Studies suggest supplements do not provide significant benefit to patients with minimal or early dry AMD. Nutritional supplements do not prevent the initial onset of AMD, nor do they improve vision already lost to AMD.
Wet AMD Treatments
Intravitreal anti-VEGF injections have been proven as an effective treatment for wet AMD. These injections reduce macular leakage and abnormal vascular growth, which helps to slow vision loss. In about 50% of patients, this treatment even improves vision. Examples of this treatment include Avastin (Bevacizumab), Lucentis, and Eylea.
For wet macular degeneration, laser treatment can help to seal the leaky vessels, but cannot repair damage that has already occurred.