There are two types of macular degeneration. Dry and wet. The dry type can lead to bad vision loss, but the wet type is the one that can quickly do so. It is the wet kind where most of the treatment modalities are focused. With the wet macular degeneration, abnormal blood vessels find their way underneath the retina and begin to leak. There’s a chemical known as vascular endothelial growth factor that is released around these blood vessels. Special medications can be given to the eye that inhibit that growth factor and allow those blood vessels to regress, to go away, so that the bleeding and the leakiness will resolve. The retina then can assume a more normal configuration. When I was in training, these medicines didn’t exist. It’s been one of the most dramatic improvements in healthcare in general since I started medicine.