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Choroidal nevi

Choroidal nevi are a benign proliferation of melanosities in the normally pigmented choroid. Because they are beneath the pigmented RPE, they often appear slate gray with feathery borders and can be completely hidden by a well-pigmented RPE when viewed with the visible light (but remain visible in the infrared). Most choroidal nevi are 5 mm or less in diameter and 1 mm or less in thickness, but they can attain a diameter of 10 mm or more, and a thickness of 3 mm or more (for reference, the average optic nerve in Caucasians is 1.5 mm in diameter). Drusen, seen as small, yellow-white inclusions in the overlying RPE, can be taken as a sign that the nevus is long-standing and, by extrapolation, absent malignant growth. (Contributed by Dr. James Walters.)

Associated Disorders

  • Bassen-Kornzweig disease
  • Cushing syndrome
  • Kearns-Sayre syndrome
  • Lawrence-Moon-Biedl syndrome
  • Mitochondrial encephalopathy with lactic acidosis and stroke-like episodes (MELAS)
  • Ocular paraneoplastic syndromes
  • Refsum disease
  • Usher syndrome
  • gastroesophageal reflux disease
  • posterior vitreous detachment
  • retinal detachment
  • systemic arterial hypertension
  • systemic lupus erythematosus