Age-related macular degeneration (ARMD) is the major cause of central vision loss in Americans aged 55 and older. The exact cause of ARMD is not known.

Dry ARMD occurs when cells under the macula break down and create deposits called drusen.  It is drusen that can make you lose some vision. Dry ARMD usually develops slowly over time, with few symptoms until it reaches an advanced stage.  The advanced stage is commonly referred to as Wet ARMD

Wet ARMD is caused by new blood vessels growing and leaking fluid in the macula. This causes damage to the macula. The macula, which is the center of your retina, plays a key role in your central vision. To visualize this, imagine the roots of a tree growing and spreading until they actually uproot a sidewalk. Then imagine rainwater seeping up through the cracks. These abnormal blood vessels (the "roots") tend to be very fragile. They often grow, and leak or bleed, causing scarring of the macula. This damage to the macula results in rapid central vision loss. Lucentis® can stop fragile roots from growing and spreading.