By Mayo Clinic News Network

Age-related macular degeneration (AMD), an eye disorder associated with aging, gradually causes loss of clear central vision. The retina is located on the inside surface of the back of your eye. The macula, in the center of the retina, is responsible for your reading and fine vision. In AMD, the macula begins to deteriorate, causing symptoms that can range from blurred central vision to a blind spot in the center of vision.

There are two types of AMD -- dry and wet.

  • Dry age-related macular degeneration. By far the more common type, dry AMD occurs when the light-sensitive tissues in the macula thin and break down. This loss of tissue gradually causes blurry central vision. Dry AMD occurs in stages — early, intermediate and advanced.
  • Wet age-related macular degeneration. In wet AMD, abnormal blood vessels under the retina begin to grow, leaking blood or fluid, causing damage to the macula. Wet AMD can cause rapid central vision loss. Wet AMD almost always begins as dry AMD.