Macular degeneration, which is atrophy or degeneration of the macular disk, accounts for about 12% of all cases of blindness in the United States and for about 17% of new cases of blindness. It’s one of the causes of severe irreversible loss of central vision in people older than age 50. It affects slightly more women than men.

Two types of age-related macular degeneration occur. The dry, or atrophic, form is characterized by atrophic pigment epithelial changes and is usually associated with a slow, progressive distortion of straight lines or edges and central visual loss. The wet, or exudative, form causes rapid onset of visual impairment. It’s characterized by subretinal neovascularization that causes leakage, hemorrhage, and fibrovascular scar formation, which produce significant loss of central vision.