Pinguecula

What it is and where it sits

A pinguecula is a yellowish, slightly raised, benign growth on the conjunctiva, and not on the cornea.

Its site is the nasal side, most commonly, or the temporal side of the sclera, near the limbus.

Causes and risk

UV light exposure, dust, wind, dry eye, and aging.

How it presents, and what it does to vision

Usually asymptomatic. It may cause mild irritation, dryness, or redness.

Its visual impact is none: it does not grow onto the cornea and it does not affect vision. That is the whole of its difference from the lesion it is confused with.

Pinguecula against pterygium

The differentiation is one line: unlike a pterygium, a pinguecula does not invade the cornea.

The pterygium in the same deck is described as a fibrovascular triangular encroachment of epithelial tissue onto the cornea, usually nasally, associated with sun and wind exposure and with aging. It may induce astigmatism and decrease vision, which is why the pterygium is more dangerous than the pinguecula. Its irritative symptoms may be treated with lubricating drops, and the surgical treatment is excision with conjunctival autograft, done for chronic inflammation, threat to the visual axis, or cosmesis.

Read side by side: the risk factors are the same on both, the site is the same nasal side, and what separates them is whether the growth has crossed onto the cornea and taken vision with it.