On a routine exam, you see the eye lesion pictured below. What is this finding?
A pterygium is a benign, triangular wedge of fibrovascular conjunctival tissue that extends from the conjunctiva onto the cornea. “Pterygium” refers to the shape of the tissue, which looks like an insect wing.
- Fun fact: a pterygium that does not extend onto the cornea is called a pinguecula!
Pterygia (the plural form of pterygium) can actively grow over a period of months, clinically marked by redness and localized thickening. When inactive, they appear white and flat, and may remain static for decades with no measurable increase in size. Visual impairment can occur when a pterygium extends more than a few millimeters onto the cornea, inducing astigmatism.
Patients with a small pterygium can be treated symptomatically for redness and irritation with artificial tears. The management of patients with larger lesions that impair visual acuity or eye movement usually involves surgical excision. Surgery should be avoided for cosmetic reasons alone, as a pterygium may recur, often with irritative symptoms.