Drusen are yellow deposits under the retina. Drusen are made up of lipids and proteins. Drusen likely do not cause age-related macular degeneration (AMD). But having drusen increases a person’s risk of developing AMD, and they may be a sign of AMD.
There are different kinds of drusen. Small drusen may not cause vision problems for a long time, if at all.
Larger drusen increase the risk for advanced AMD, which can result in vision loss.
What Causes Drusen?
Drusen occur naturally with age. The exact relationship between degenerative macular disease and drusen is not clear. However, having large drusen is a sign of AMD.
Drusen of the Optic Nerve
Drusen can also occur in the optic nerve. These drusen are made up of protein and calcium salts and generally appear in both eyes. Unlike the drusen associated with AMD, optic nerve drusen (also known as optic disc drusen) are not related to aging, may be inherited, and typically appear in children. Optic nerve drusen usually do not affect vision, but some patients with these drusen may lose peripheral (side) vision.
Most people with drusen do not have any symptoms. Often, a routine eye exam will incidentally reveal their presence. A few small drusen are not a symptom of eye disease. However, the presence of a large number of larger drusen is an early sign of dry age-related macular degeneration (AMD). The symptoms of AMD include hazy vision, difficulty seeing when going from bright light to low light, and a blank or blurry spot in your central vision.
Optic nerve drusen also often do not produce symptoms. However, some patients with optic nerve drusen experience vision problems, including loss of peripheral (side) vision and temporary flickering or graying out of their vision.
Who Is at Risk for Drusen?
Drusen are typically a result of aging and are commonly found in people age 60 and older. Caucasians (white people) are more likely to develop drusen, as well as age-related macular degeneration (AMD). Large drusen are associated with AMD. Risk factors for AMD include a family history of the disease, smoking and being white. Other risk factors are obesity, high cholesterol (fat in your bloodstream) and high blood pressure.
The risk of developing optic nerve drusen is also increased for white people and those with a family history of drusen.
Drusen are detected during a dilated eye exam. To check your eyes, your ophthalmologist will dilate (widen) your pupils using dilating eyedrops and examine your eyes with an ophthalmoscope, a device that allows him or her to see the retina and other areas at the back of the eye. This examination will allow him or her to see if drusen are present.
If your ophthalmologist detects large drusen, he or she may have you use an Amsler grid to check for macular degeneration symptoms such as wavy, blurry or dark areas in your vision. If your ophthalmologist thinks you have optic nerve drusen, he or she may order additional imaging tests to confirm the diagnosis.
Small drusen do not need to be treated. If your ophthalmologist finds small drusen during a routine eye exam, he or she may want to watch them regularly to make sure they do not develop into large drusen.
Because larger drusen are a sign of age-related macular degeneration (AMD), your ophthalmologist will follow the AMD treatment appropriate for you. Trying to eliminate the drusen will not improve your AMD.
If you have optic nerve drusen without symptoms, you should be monitored regularly. There is no treatment for optic nerve drusen. In rare cases where choroidal neovascular membranes (new blood vessels growing under the retina) develop, treatment may be appropriate.