What is Age-Related Macular Degeneration (AMD)?
The macula is a small area of the retina located directly at the back of the eye. While the entire retina receives light rays, the macula is responsible for central vision, including fine detail and colours. When degenerative processes affect this region, the vision can be decreased. Sometimes abnormal new blood vessels grow through these thin degenerative areas, causing leakage of fluid, bleeding and scar tissue formation (wet AMD). Sometimes the retina simply becomes thinner and sees less well (dry AMD). Symptoms include decreased vision, blind spots in vision, and distortion (straight lines appearing curved or wavy). AMD is diagnosed by an examination, and by photography. The ophthalmologist examines the eye for signs of degeneration, leaking fluid, bleeding or scar tissue formation. A series of photographs, called a fluorescein angiogram, is taken to identify any leaking blood vessels. Measuring the retinal thickness with OCT (optical coherence tomography), can help to diagnose and monitor AMD.
Is AMD treatable?
There is no cure for the degenerative aspect of AMD. However the Age Related Macular Degeneration Study has indicated that supplements with antioxidants may help prevent progression of dry AMD. Anti-VEGF (vascular endothelial growth factor) agents to stop the abnormal blood vessels from leaking have been shown to be effective when injected in the eye to treat wet AMD. PDT laser has been found to be a useful adjunct.
What should be done after the initial visit or treatment?
The goal is to save as much vision as possible. Sometimes, after treatment for wet AMD, the vision is improved, but sometimes we treat to prevent further vision loss. Periodic visits are recommended and treatments given whenever a change is noted in the vision, the exam, or imaging. If the vision is decreased in both eyes, low vision devices may be tried. Magnifying glasses, telescopes, and closed-circuit televisions are often the most useful. Although the vision loss with AMD can be frustrating, it is not expected that a total loss of vision will occur. Peripheral vision can be used even in most of the advanced cases.