A freckle in the eye is called a nevus in medical terminology. The word nevus (the plural form of this is nevi) is a medical word that refers to a mole or freckle. It is an area of your body that is typically darker in color or more pigmented than the rest of the surrounding cells of the body. We most commonly see freckles or moles on our skin, but you can also get a freckle in the eye. A nevus is a benign lesion meaning it is not a cancer and it does not grow significantly or cause harm. Just how a freckle on your skin can happen in many different places, a freckle in the eye can also happen in different parts of the eye including the iris, the conjunctiva (the white part of your eye), the choroid, and the retina. The choroid and retina are tissues in the back of the eye that only an eye doctor can see during a dilated eye exam. In the vast majority of cases, a nevus, or freckle in the eye, is not dangerous. It is important that they are monitored for change in size or other characteristics with regular dilated eye exams.
Nevi in the eye are most common in the choroid which is in the back of the eye, close to the retina. A nevus is formed by a collection of cells (called melanocytes) which produce a substance called melanin that gives color or pigment to the skin. These nevi are called choroidal nevi and can only be viewed by an eye doctor during a dilated eye exam. In the choroid a nevus can be different colors including brown, gray and yellow and may have a speckle appearance. As with all nevi, they are typically benign but should be monitored to ensure there is no significant change in size or other characteristics. Nevi are often monitored by an eye doctor using regular eye exams and photographs of the retina to watch for signs of possible progression to a choroidal melanoma, although this is uncommon. A choroidal melanoma is a malignant or cancerous lesion which needs treatment to prevent it from spreading. Signs which may be concerning for progression to a melanoma include a lesion that is raised or elevated, associated with fluid or swelling, or orange in color.
It is common to have pigmented, or darker colored, areas on the colored part of the eye, also known as the iris. Pigmented areas of the iris are more noticeable in people with light colored eyes like blue or green. They are seen as brown areas on an otherwise light colored eye. Small pigmented areas on the iris are likely freckles which are caused by a collection of melanin (a brown colored pigmented) in that area. These areas are benign with no risk of turning into a cancerous lesion. Larger pigmented areas are potentially iris nevi which are a collection of melanocytes causing the increase in pigment. Nevi are also benign with a small chance of turning into a iris melanoma and should be monitored by an eye doctor for changes in size or shape. An eye doctor will typically monitor a nevus with periodic photographes and/or measurements to ensure there are no significant changes.
The conjunctiva is the clear covering or “skin” of the eye which covers the white part of the eye (called the sclera). The conjunctiva can also develop areas of pigment or nevi due to a collection of melanocytes within the conjunctiva. These typically appear as differing shades of brown but can sometimes be a lighter yellow color. Like nevi in other areas of the eye, these lesions are typically benign but should be monitored by an eye doctor with periodic examinations and/or photographs to ensure there are concerning signs for transformation into a cancerous lesion, or melanoma.
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Treatment for Nevi
Nevi are benign lesions and typically require only observation. Treatment is not recommended unless they transform to a more dangerous malignant lesion which is uncommon. If transformation to a melanoma does occur treatment may include surgery, laser, radiation or sometimes removal of the eye. The treatment recommended will depend on the size and location of the melanoma.
Shields CL, Shields JA, Kiratli H, et al. Risk factors for growth and metastasis of small choroidal melanocytic lesions. Ophthalmology 1995;102:1351–1361
Shields CL, Furuta M, Berman EL, et al. Choroidal nevus transformation into melanoma: analysis of 2514 consecutive cases. Arch Ophthalmol 2009;127:981–987
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