What is a pterygium?

A pterygium is a benign, triangular-shaped growth of the conjunctiva that grows onto the cornea. The conjunctiva is the thin clear layer of tissue that lies over the white of the eyeball. A pterygium is made up of collagen and fibrovascular tissue that grows from the conjunctiva and eventually advances onto the cornea (the clear outer covering of the eyeball). Pterygia are more commonly located on the inner or medial portion of the eye.

What causes a pterygium?

The exact cause is unknown. However, it has been associated with excessive sun, wind, dust, and sand exposure. As such, protecting your eyes from the elements can help slow the growth of a pterygium. Even though a pterygium is considered a benign growth of the eye, it can become an annoyance to some patients due to dryness or from a cosmetic standpoint. Should you notice any type of growth on the eyeball, it is important to have it properly diagnosed by your local optometrist.

What can be done to treat a pterygium?

Normally there is no discomfort associated with a pterygium and it is asymptomatic; hence nothing is done for it. With mild to moderate pterygia, where the patient has symptoms, artificial tear supplements and/or mild anti-inflammatory drops can be used to minimize symptoms. If a pterygium becomes very large, irritated or encroaches on the visual access, your doctor of optometry will refer you to anophthalmologist to surgically remove the excess tissue. Unfortunately, a pterygium will often grow back.

What are the risk factors for pterygium if left untreated?

As a pterygium grows over the surface of the cornea and towards the center of the eye, it becomes more problematic. Patients will notice that their eye constantly feels irritated and there may be a foreign body sensation. The pterygium may also become more noticeable to people looking at the patient. If a pterygium becomes very large, irritated or encroaches on the visual access, your optometrist will refer you to an ophthalmologist to surgically remove the excess tissue. Unfortunately, even with complete removal, a pterygium can reoccur.

Image by Jmvaras José Miguel Varas, MD (Own work) [GFDL ( or CC BY 3.0 (], via Wikimedia Commons

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