Small, hard, yellow protein deposits that appear under the nourishing layer of the retina called the retinal pigment epithelium (RPE) are called drusen. Some small drusen are common in people as they age, even in the absence of disease. However, the presence of drusen often indicate the early stages of age-related macular degeneration (AMD). When drusen become larger, softer, and more vaguely shaped, there is a greater risk that an advanced stage of AMD will develop and vision loss will occur. Drusen are able to be seen during a comprehensive eye exam. 

Scientists do not understand the exact relationship between drusen and the progression of AMD to advanced stages. The Complications of AMD Prevention Trial (CAPT) recently followed patients who had large drusen in both eyes. Lasers were used to treat the drusen in one eye, while the other eye remained untreated. After five years, it was found that AMD progressed equally in both treated and untreated eyes. CAPT concluded that laser treatment of drusen does not stop vision loss. At this time, drusen are not treated or removed. However, drusen do sometimes unexplainably resolve themselves.