Choroidal Nevus

What is Choroidal Nevus?

A choroidal nevus is a flat, benign and brown-green colored area at the back of the eye, often seen in the pigmented layer beneath the retina called the choroid. A nevus can appear in the eye just like a raised freckle or mole occur on the skin.  Choroidal nevus occurs in about 4.6-7.9% of the population. Light coloured eyes and skin tend to have higher risk due to the exposure to ultraviolet light.

 

What are the symptoms and how to diagnose it?

Most patients experience no symptoms. Typically, choroidal nevus is found on routine dilated eye examinations by an optometrist or an eye specialist using specialised tools to see inside the eye. Diagnostic tests may include ultrasound, photographs, optical coherence tomography (OCT) and/or a fluorescein angiography to determine the extent and progression of the choroidal nevus.

OCT of Choroidal nevus

OCT of Choroidal nevus

Is it cancerous?

A choroidal nevus is usually safe, however some have very a small potential to grow into a malignant melanoma (eye cancer). During an eye examination, an experienced eye specialist would be able to identify the following factors associated with potential melanoma growth:

  • Visual symptoms (Blurry vision, floaters, flashes, seeing waving image, colour changes)
  • Rapid growth
  • Lesion thickness greater than 2.0 mm
  • Fluid under the retina
  • Orange pigment
  • Posterior lesion margin touching the optic nerve area
  • Possibly associated with bleeding

 

Can it be treated?

Most benign choroidal nevus do not require treatment but need to be continually monitored for any signs of change. If your choroidal nevus becomes suspicious, your specialist may recheck your eyes more frequently.