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 Macular degeneration is a leading cause of severe visual loss in people over the age of 65. It is only rarely seen in people younger than 55.
The macula is the area in the very center of the retina. The retinal photoreceptors called cones are concentrated here. Your central vision, the sight that allows you to read, drive a car, and recognize faces, happens here. The retinal photoreceptors called rods are concentrated in the peripheral retina. Night vision and side vision takes place here.
There are two general types of macular degeneration. Atrophic or dry macular degeneration is the most common type.
 Dry Macular Degeneration
The outer layer of the retina, the retinal pigmented epithelium (RPE) becomes thin and unhealthy. Abnormal structures called drusen may begin to be visible. Vision loss, if it occurs, is often gradual. Although laser treatment for drusen has been the subject of research, there is presently no established medical, surgical or laser treatment for atrophic macular degeneration.
Exudative or wet macular degeneration is a less common, but more devastating variety of macular degeneration. A break or opening is presumed to occur in the RPE allowing blood vessels to form and grown beneath the retina. These blood vessels are abnormal and they leak both blood and plasma underneath the retina. Called a neovascular membrane, the presence of these blood vessels can permanently destroy some or all of the macula, and can do so very rapidly. Most of the exciting advances in macular degeneration treatment have occurred here. Surgery to remove the neovascular membranes, thermal and light activated laser treatments, and injectable medications such as Macugen are all designed to prevent devastating visual loss.
People who have wet macular degeneration have increased systemic risk factors for their general health. Patients with wet macular degeneration are generally older and are more vulnerable to serious events such as strokes and heart attacks. These events can cause significant difficulties in life as well as death. Individuals with wet macular degeneration have a much higher rate of general medical disease than similar aged patients without wet macular degeneration. These patients have a 12% higher risk of stroke, a 32% higher risk of hypertension and a 36% higher risk for elevated blood lipids. If you have this type of macular degeneration it is very important for you to be under the active care of a family physician.
 Wet Macular Degeneration
Macular degeneration causes damage to your central vision. In all but the most devastating cases your peripheral or side vision is preserved. Risk factors for macular degeneration include family history, sex  (women are more susceptible than men), light colored eyes and smoking. Early macular degeneration is often present without any symptoms. Much like glaucoma, many people do not realize they have a problem until their vision is quite blurred and irreparable damage is done.
Detection of macular degeneration is accomplished with a thorough eye exam. If macular degeneration is detected color photographs of your macula may be taken. If the macular degeneration is severe or if the risk for bleeding is high a fluorescein angiogram may be indicated. This test is performed in the office. A special vegetable-based dye is injected into your veins.  The dye travels to the blood vessels in your eye. The dye highlights all of the normal and abnormal blood vessels in your eye, and special photographs are taken.
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