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As many as 20 million Americans suffer from age-related macular degeneration (AMD), a disease of the eyes that, if left untreated, can result in severely impaired vision. In up to 10 percent of cases AMD can cause total blindness.

What is Age-Related Macular Degeneration?

Identified in Ancient Greece as early as 300 BC, but not well understood until the mid-19th century, modern AMD research has led to a number of treatment options, some of which are even giving hope to those stricken with the most advanced form of the disease that almost always causes blindness.

Ninety percent of newly diagnosed cases of AMD are classified as “dry” and are much more treatable, especially if caught early in the degenerative process. If left untreated, dry cases can become “wet” AMD and vision can deteriorate rapidly. While only about ten percent of AMD cases turn into the “wet” form, 90 percent of AMD-related legal blindness is caused by the wet form.

Signs, symptoms, and diagnosis

AMD can be diagnosed years before a patient experiences symptoms.

AMD can be diagnosed years before a patient experiences symptoms. The first symptom a person may notice with AMD is blurred central vision. For example, if looking at the face of an analog clock, the center of the clock and hands would be blurry while the numerals and perimeter would be in sharp focus. Some people may also see a dark area or wavy lines in the center of their visual field.

Without good central vision, a person’s ability to read, drive, recognize faces, and perform other visual tasks we take for granted is severely limited. AMD may affect only one eye, but a person who has AMD in one eye is more likely to develop it in the other eye than someone who does not have it at all.

The disease begins in the area of the retina known as the macula. The retina is the light-sensitive layer of tissue at the rear of the eyeball, and the macula is centrally located on the retina, right where light rays are focused via the eye’s lens at the front of the eyeball. As we age, the quality of the retina and macula tissues deteriorates, and small deposits of proteins called drusen form. These proteins block light and lead to degraded central vision. 

Treatment options for dry and wet AMD

While there is no known cure for AMD, when it is diagnosed early, it can sometimes be stopped in its tracks or at least slowed down with little loss of vision resulting. At this early, “dry” stage, treatment options include diet and lifestyle changes, as well as supplementation with a formula known as AREDS, which includes vitamins A, C, and E, plus zinc and copper. A couple of pharmaceuticals (pegcetacoplan and avacincaptad pegol) have been developed and released over the past couple of years that may be prescribed for dry AMD that has begun to take a more marked toll on vision. It is recommended that patients with a history of smoking take AREDS 2, which contains lutein and zeaxanthin. AREDS and AREDS 2 can be found over the counter and online.

Patients are encouraged to seek therapy for the emotional toll of lost vision.

If the disease progresses to the much more advanced and detrimental “wet” stage, which is always preceded by the dry stage, treatment becomes more aggressive in order to save as much vision as possible. The wet stage is characterized by the leaking of blood and other fluids from abnormal growth of blood vessels around the retina, blocking light from reaching the macula. Additionally, blood is toxic and damaging to the rods and cones that are the cellular interpreters of light and color embedded in the retina. 

The standard treatment for wet AMD is injections into the eye of a medication that blocks the molecule that causes abnormal vessel growth. As many as eight to twelve injections per year may be necessary to slow or stall the deterioration of vision. In some rare cases, laser therapy may be used. Ironically, one of the side effects of injections can be an increased risk of developing cataracts.

Despite treatment, some cases of wet AMD will result in severely compromised vision or even legal blindness in the affected eye. At that point, patients are encouraged to seek therapy for the emotional toll of lost vision, to learn techniques for maximizing the use of undamaged peripheral vision, and to use various tools that help to enhance what vision remains.

Prevention and early detection are key

The earlier it is diagnosed, the greater your chances of preserving your vision.

Diets high in saturated fats, cigarette smoking, cardiovascular disease, being over the age of 50, poor nutrition, a sedentary lifestyle, head injuries, and infections can all be contributing risk factors for AMD.  Genetics can sometimes play a part, so while you may be more at risk if an immediate family member has AMD, you do not escape risk if no one in your family has been diagnosed with it. Studies have shown that obesity can raise the risk of AMD. You can reduce your risk of AMD by wearing a hat, sunglasses and other sun protection while outdoors, quitting smoking, and eating leafy green vegetables like spinach, kale, and Brussels sprouts.

If you have a family history of AMD and are over the age of 40, it’s a good idea to see an optometrist or ophthalmologist every year or two to be screened for early signs of AMD. Otherwise, 50 is a good age to begin yearly screenings. The earlier it is diagnosed, the greater your chances of preserving your vision. It might also be a good idea to keep an Amsler Grid on your bathroom mirror or on your fridge. This grid of straight lines with a bold dot in the middle can help you detect early signs of AMD. When using the Amsler Grid, if you see blurry patches, wavy lines, or dark areas instead of a grid of straight lines, these are early warning signs. While you stare at the central dot, look for any of the mentioned abnormalities.

SoHum Health has recently begun mobile optometry services in Garberville, where they perform screenings for AMD as part of a standard appointment. Garberville Optometry sees patients on their mobile unit located behind Garberville Pharmacy at 286 Sprowl Road on Tuesdays, Wednesdays, and Thursdays. To schedule an appointment for an AMD screening, please call (707) 923-3921 x1221.

Ann Constantino, submitted on behalf of the SoHum Health’s Outreach department.