What is the Difference Between a Pterygium and a Pinguecula?

1:38

Video Transcript

What is the difference between a pterygium and a pinguecula?
Hi, I’m Dr. Allan Hayes, specialist cataract, refractive, and pterygium surgeon here on the Sunshine Coast. Both conditions are growths on the surface of the eye — specifically on the conjunctiva, the clear membrane that covers the white of the eye — and both are strongly associated with UV exposure. So if you live on the Sunshine Coast, you’re in a high-exposure environment. The key difference is this: a pinguecula stays on the white part of the eye. It’s a yellowish-white deposit, slightly raised, and while it can be irritating or cosmetically noticeable, it doesn’t affect the cornea directly. A pterygium goes further. It extends onto the cornea — the clear dome at the front of the eye — and in doing so it can distort the corneal surface, affect vision, and grow toward the line of sight if left untreated. Both conditions can cause discomfort, redness, and cosmetic concern — and both can be addressed surgically. I’d encourage you to take our symptom quiz or book an appointment with me if you’re unsure which applies to you.

What is the Difference Between a Pterygium and a Pinguecula?

These two conditions are frequently confused — and for good reason. They share common causes, similar appearances, and can occur in the same patient at the same time. Understanding the distinction, however, is important for knowing when and why treatment may be recommended.

What is a pinguecula?

A pinguecula (pronounced pin-GWEK-yoo-lah) is a yellowish-white, slightly elevated deposit that forms on the conjunctiva — the thin, transparent membrane covering the white of the eye (sclera). It typically appears on the side of the eye closest to the nose or, less commonly, the temple side.

Pingueculae are caused by cumulative UV exposure, wind, and dust — making them extremely common in sun-exposed populations such as those living in Queensland. They do not extend onto the cornea and do not directly threaten vision, but they can cause:

• Irritation and foreign body sensation
• Dryness (they can disrupt the tear film)
• Recurrent redness and inflammation (pingueculitis)
• Cosmetic concern

What is a pterygium?

A pterygium (pronounced teh-RIJ-ee-um) begins like a pinguecula — on the conjunctiva — but goes further. It extends as a wing-shaped fibrovascular growth onto the cornea (the clear dome covering the front of the eye). This is the defining difference.

Because it involves the cornea, a pterygium carries additional implications:

• It can distort the corneal surface and induce or worsen astigmatism
• It can reduce clarity of vision if it grows toward the visual axis
• If left untreated, it can progress significantly — in rare cases reaching the pupil
• The irregular tissue changes the shape of the eye’s surface in a way a pinguecula does not

Same causes, different anatomy

Both conditions share the same primary cause: chronic UV radiation exposure. Queensland’s intensity of sunlight, outdoor lifestyle, and water-reflected UV make it one of the highest-risk regions in the world for both conditions. UV-protective eyewear is strongly recommended for prevention and to slow progression.

Can both be treated surgically?

Yes. Both pterygium and pinguecula can be addressed with the Signature No-Stitch Pterygium Surgery if they are causing sufficient symptoms or cosmetic concern. A consultation with Dr Hayes will determine which condition is present and whether treatment is appropriate.

Could they be anything else?

Although sun damage changes of the eye are usually a pterygium or pinguecula, occasionally types of skin cancers can develop in a similar pattern. These are known as ocular surface squamous neoplasia (OSSN), and are the same as some skin cancers but occur on the surface of the eye. Often these have different characteristics to a pterygium or pinguecula, but sometimes they can be indistinguishable from these less sinister causes. Because of this risk, removal with microscopic analysis is the only way to be sure if the spot on the front of the eye is benign or malignant.

Key Takeaways

• A pinguecula is a yellowish-white deposit on the white of the eye; it does not affect the cornea
• A pterygium extends onto the cornea and can affect vision and induce astigmatism
• Both are caused by chronic UV exposure and are common in Queensland
• Both can be treated surgically if causing symptoms or cosmetic concern
• More worrisome, malignant, lesions can mimic both a pterygium and pinguecula.

Not sure if you have a pterygium or a pinguecula?

Take our symptom quiz

Book a consultation with Dr Rylan Hayes at The Vision Surgeon, Maroochydore.

References

• American Academy of Ophthalmology. Pterygium — Preferred Practice Pattern. aao.org
• Panchapakesan J, et al. Five year incidence of pterygium and pinguecula — the Blue Mountains Eye Study. Invest Ophthalmol Vis Sci. 1998.
• Coroneo MT. Pterygium as an indicator of UV exposure. Br J Ophthalmol. 1993.