Ten years ago, the best available treatment for AMD was photodynamic therapy--in which an intravenous drug (injected into a vein) and laser are used to seal off leaking blood vessels. Past studies have found that just one year after diagnosis, less than 15 percent of patients given this therapy alone retain 20/40 vision, and up to 40 percent decline to 20/200 vision. Without any treatment, less than 10 percent of patients retain 20/40 vision at one year, and up to 75 percent of untreated patients decline to 20/200 vision.