Age Macular Degeneration (AMD)

Age Macular Degeneration (AMD) is a degenerative disease affecting the macula, the central portion of the retina. The macula is responsible for detailed and sharp vision when we read, drive or recognize faces.

AMD usually appears in people over 60 years of age, and is a major cause of permanent loss of vision in the elderly. Different factors determine the age of onset, severity and progression.

Among these are genetics (having relatives affected with AMD), lifestyle habits including diet (poor in fresh vegetables and fruits), lack of physical exercise and smoking. If a person is obese or has hypertension, these conditions will also increase the risk of getting AMD.

Broadly speaking, AMD can be divided into wet (neovascular) and dry (atrophic) AMD.

Wet (neovascular) AMD

Here, a membrane containing abnormal vessels grows under the macula. Vessels in this membrane can burst at anytime and bleed causing a severe vision loss. They also tend to leak causing swelling of the retina and distorting vision.

As a patient you may notice that there is a blur in the very center of your vision (a smudge). Its size will depend on the area affected. If it recently got larger, you should seek help as soon as possible (see treatment below).

Patients also notice that objects and lines that should be straight are curved. The waviness is visible when looking at the edge of doors or tiles on the wall, or at a crossword puzzle. There are many causes for this, and so just having one of these signs does not mean you have AMD but you should see an EyeMD so that you can find out. If there has been a recent change, do not wait too long to get a professional opinion.

Dry (geographic or atrophic) AMD

Here, there is a progressive loss of a layer of cells under the retina called the retinal pigment epithelium (RPE). Without these cells, the retina slowly dies away.

As a patient you will see a central gray spot which slowly gets larger over many years. This form of AMD, the most common, does not cause vision loss as quickly or as bad as the wet AMD.

Sometimes though, you can pass from one form to the other….Today there are treatments available for wet AMD. For dry AMD, some are being developed but it will take still a few years.

It is important though to treat you as early as possible after the wet AMD has caused a drop in vision or more distortion. For this reason, we recommend that you test each eye every day. One of the easiest ways of doing this is to look at a grid made up of vertical and horizontal lines. The AMSLER GRID has a point at its center. When you fix your vision on this point, you will see the lines around it as being straight or crooked.

If they are crooked, wavy or a spot has appeared where there was none before, it could be a sign of a membrane appearing or acting up. You should seek the opinion of an EyeMD as soon as possible.

The Eye Exam

Your ophthalmologist or EyeMD will do a complete exam, checking your vision, and looking into your eye with an ophthalmoscope after dilating your pupils. He will also do some tests such as the a OCT and in some cases will suggest that fluorescein angiography and autofluoresence photography be done to better understand the changes in your eye, and get some idea of your risk of getting worse. .

Treating Wet AMD

If you have wet AMD, a number of possible treatments can be offered depending on your condition.

The most common approach is to treat with anti-VEGF antibodies injected into your eye, roughly on a monthly basis until the membrane is gone. Then the frequency of injections diminishes but you will still need frequent and adequate follow-up. The anti-VEGF agents uses are ranibizumab (Lucentis), bevacizumab (Avastin), aflibercept (Eylea). In some patients, after initial treatment with one of the anti-VEGF agents, a laser treatment is proposed often in the form of photodynamic therapy. With this treatment, a special dye is injected into the vein causing the abnormal (neovascular) vessels to shut down. The product used is Verteporfin (Visudyne). Other options exist in specific cases including radiation to the area of the macula.

For most patients, the treatment given will prevent further loss of vision and a moderate gain. This is why it is so important to seek early advice for diagnosis and treatment.

Treating dry AMD

There is currently no cure for dry AMD.

In patients with high-risk signs in their eyes, or a wet AMD in the opposite eye, it may be worth while taking anti-oxidants and multivitamins. A special formulation has been proposed in the AREDS study carried out at the NEI in the United States.

Some healthy habits like a balanced diet, regular exercise, not smoking, are great protective factors some of the easiest and most pleasant to deal with. Check with your ophthalmologist what the best approach is to your case and how best to prevent progression.

Macular degeneration is currently the subject of a great deal of research. Newer and better treatments are on their way. For more information on AMD visit the following links: clinicaltrials.gov and amd.org