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What Is Macular Degeneration?

Age-Related Macular Degeneration (ARMD) is the No. 1 cause of vision loss in the U.S., with more than 13 million Americans showing some sign of the disorder. ARMD is uncommon in folks younger than 55. If you are over 65, macular degeneration may already affect your central vision - the vision you need for reading close work like sewing. ARMD occurs in two forms, dry and wet. The less-common wet form of ARMD requires immediate medical attention - any delay in treatment may result in loss of your central vision. It is important to know that most folks with ARMD do not become totally blind. Moreover, regular examinations can detect progression of ARMD so that preventive treatment can be offered. Finally, recent innovations in ARMD can halt or slow progression of retinal changes.

What Causes Macular Degeneration?

In order to understand macular degeneration let's get to know the macula (from the Latin meaning 'spot'). The macula is the most important region of the visual anatomy. It is a very small portion of the retina and is about the size of a pencil eraser. The macula is loaded with photoreceptors, and that enables you to read, watch television, drive, sew — anything that requires focused, precise vision. Outside of the macula there are far fewer photoreceptors and image resolution is much poorer. Although these uninvolved portions of the retina can continue to process images along the edge your field of vision, the tissue damage caused by ARMD distorts or obscures part of the crisp central images that your eye transmits to your brain.

In the dry form of ARMD, tiny yellow deposits develop beneath the macula, signaling a degeneration and thinning of nerve tissue. A small number of cases develop into the wet, or neovascular, form of ARMD, in which abnormal blood vessels grow beneath the macula. As these vessels leak blood and fluid onto and underneath the retina, retinal cells die - causing blurs and blank spots in your field of vision.