A choroidal nevus is a freckle or mole that appears inside the eye or on the eye's surface. Sometimes detected during a dilated eye examination, these pigmented spots are usually flat and brown in color. Choroidal nevi are commonly found in the choroid, a blood vessel-rich layer lying between the retina and the sclera. Although they are not necessarily a "normal" finding in our eyes, they are quite common and usually benign. Nevi vary from patient to patient but most look very similar and have certain traits that eye doctors are very familiar with. Your doctor will document this finding in your chart if it is detected during a routine eye exam.
Choroidal nevi are not usually harmful. However, just like a freckle on your skin, if it changes in color, size or shape you should follow your eye doctor’s recommendations on how to treat, when to come back, or how to observe it in the future.
Typical evaluation involves taking a digital photograph for documentation. Your doctor will then schedule you to come back in 3 to 6 months to look for possible changes. If your doctor has seen you for several years, then he or she may feel comfortable monitoring the nevus every 12 months. If it appears unusual, however, you may be asked to return in a shorter period of time.
Choroidal nevi are benign, however, your eye doctor is trained to watch closely for the development of a choroidal melanoma, a malignant tumor found in the eye. In rare cases, the nevus must be biopsied and examined for melanoma (cancer) cells. Choroidal melanomas are malignant tumors and must be treated to avoid metastasis, which can be fatal.