Retinal Conditions

Choroidal Nevus

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​What Is a Choroidal Nevus?

A choroidal nevus is a common, pigmented lesion found inside the eye — specifically under the

retina in a layer of tissue called the choroid. It is similar to a freckle or mole on your skin and arises from pigment-containing cells called melanocytes, which produce the pigment that colors our hair, skin, and eyes.

 

It may appear brown, gray, or have multiple colors. Some nevi appear non-pigmented (amelanotic) and may look yellowish rather than brown. Nevi can also develop overlying yellow deposits known

as drusen.

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What Causes a Choroidal Nevus?

A nevus forms when melanocytes – the cells responsible for pigmentation – clump together rather than spread evenly through body tissue. There may also be an association between exposure to

ultraviolet (UV) light and developing nevi. Wearing sunglasses that protect your eyes from UV light

is always recommended.

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How Common Is It?

Choroidal nevi are relatively common. The estimated prevalence in the United States is about 5% or

1 in 20 adults. They are most often found during routine eye exams. Most people never know they have one unless their eye doctor discovers it. People can be born with a choroidal nevus, or one may develop it later in life. Some eyes may have more than one nevus, and nevi may also be found in both eyes.

 

Does a Choroidal Nevus Cause Symptoms?

Most choroidal nevi do not cause any symptoms and are discovered incidentally during a routine eye exam. However, in some cases a nevus may cause:

• Blurred vision — particularly if the nevus is located at the center of the retina (macula)

• Flashes of light

• Floaters 

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Is a Choroidal Nevus Dangerous?

Most choroidal nevi are benign or harmless and never cause health problems. However, like a skin mole, a choroidal nevus could potentially transform into a type of cancer called choroidal melanoma. This is why it’s so important to monitor your nevus with a retina specialist. The estimated rate of

transformation is approximately 1 in 9,000 per year.

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How is a Choroidal Nevus Monitored?

Because nevi can change over time, regular monitoring with dilated eye exams by an ophthalmologist is essential. Your doctor will compare exams and imaging of the nevus over time to check for changes in size, shape, or appearance. Imaging modalities may include: photographs, scans, and ultrasounds.

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How is a Choroidal Nevus Treated?

Benign choroidal nevi do not require any treatment. Nevi should be observed and monitored by

your retina specialist with repeat exams and imaging to document changes.

 

Suspected choroidal melanoma: If a nevus demonstrates growth or has suspicious features, your

ophthalmologist will refer you to an ocular oncologist (a specialist in eye tumors). If confirmed as

a choroidal melanoma, treatment options may include radiation, laser therapy, surgery, or in some

cases, removal of the eye.

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What Should a Patient Do?

• Keep all scheduled eye appointments. Regular monitoring is the most important thing you can do!

• Report any new symptoms to your retina specialist promptly: new flashes, floaters, blurred vision, or any other changes in your vision.

• Protect your eyes from the sun and UV light.

Key takeaway: Even if you feel nothing unusual, it is important to have your choroidal nevus examined and monitored by an ophthalmologist regularly. While most nevi are harmless, only regular dilated fundus eye exams can confirm this and ensure changes are caught early.

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Sources: American Academy of Ophthalmology (aao.org) | American Society of Retina Specialists (asrs.org)