Stages of AMD

There are two types of age-related macular degeneration (AMD), usually described as either “dry” or “wet” (see Figure below). Both types of AMD can cause severe vision loss, affecting central vision but sparing the peripheral (side) vision.^1,2 Earlier diagnosis and appropriate treatment help maintain better vision.³

• “Dry” (atrophic, or non-exudative) AMD:^4,5 In the dry type of AMD, areas of the macula get thinner (atrophy), and deposits of fats and protein, called drusen, develop under the tissues of the retina.^4,5 Approximately 80% of people with AMD have the dry form, which can slowly progress to late- (geographic atrophy, meaning the cells in the center of the retina are getting thinner) or end-stage disease.² Sometimes, people with dry AMD can develop the “wet” advanced form in later disease.^1-3,6-8
• “Wet” (neovascular, or exudative) AMD: In the wet type of AMD, abnormal blood vessels (neovascular means new blood vessels) grow under the tissues of the retina.^4,5 These abnormal blood vessels can leak blood or other fluid (exudates), causing scarring of the macula.⁴ Although the wet form is less common, vision loss can be faster and more severe; about 90% of cases of legal blindness caused by AMD are due to this form.²