Disease Overview

Macular degeneration is caused by deterioration of a a critical portion of the retina, which is the tissue that lines the back of the eye and translates light from the images we see into electrical impulses, which are sentt via the optic nerve to the brain, which interprets them as sight. This critical area of the retina is known as the macula, and is responsible for capturing detailed information from the center of our visual field, along with color perception and the ability to perceive contrast. If the macula deteriorates, the resulting loss of detailed, central vision reduces our visual acuity, making it much harder or even impossible to read, drive a car, recognize faces, play sports, and see objects in fine detail. The accompanying reduction in color perception makes things look dull.  Eventually, if the area of central vision loss becomes too extensive, even using magnifying devices can fail to provide enough useful sight and only peripheral vision remains.

When the cells of the macula deteriorate, images are not received correctly. In early stages, macular degeneration does not affect vision. Later, if the disease progresses, people experience wavy or blurred vision, and, if the condition continues to worsen, central vision may be completely lost. People with very advanced macular degeneration are considered legally blind. Even so, because the rest of the retina is still working, they retain their peripheral vision, which is not as clear and sharp as central vision.

The macula is only about 2.1% of the entire retina. The rest of the retina is the peripheral field and is unaffected by macular degeneration. Though the macula is such a small portion of the retina, almost half of the visual cortex is dedicated to processing information from the macula, highlighting just how important to human vision this tiny little part of the retina is.