A pterygium is a pinkish, triangular-shaped tissue growth on the cornea. Pterygia are more common in sunny climates with patients typically in the 20 to 40 age group. Studies suggest where sunlight is strong, wearing protective eyeglasses, sunglasses, and/or hats with brims may help reduce the incidence of pterygium.

Because a pterygium is visible, many individuals want to have it removed for cosmetic reasons. It is usually not too noticeable unless it becomes red and swollen from dust or air pollutants. Surgery to remove a pterygium is not recommended unless it affects vision, causes significant discomfort, or if the ophthalmologist notes that it has a suspicious appearance. If a pterygium is surgically removed, it may grow back, particularly if the patient is younger than 40 years of age and does not reduce risk factors, such as direct sun exposure or chronic irritation from allergies or a dusty or dirty work environment.

In some cases, if the pterygium is small, not growing and not symptomatic, observation is acceptable. The doctor will check for signs of growth or a change in appearance, either of which would be a reason to recommend removal.

Simple Excision

Many eye surgeons will remove a pterygium with the simple excision technique. Using a topical or local anesthetic, the pterygium is dissected from the surface of the eye.

The ‘defect’ that is left will gradually heal. While simple excision is the least difficult technique to perform, it is associated with more discomfort and a higher chance of recurrence than other techniques.

Excision with Amniotic Graft

An example of a pterygium.

A technically more difficult method is to remove the pterygium as above but to then cover the defect with a graft made of amniotic tissue, which is harvested from placental tissue. This tissue has natural healing properties, allowing the eye to recover faster and with less pain, and the risk of recurrence is lower than with simple excision. The graft can usually be attached to the surface of the eye using a fibrin glue and without the need for sutures. Sometimes this technique is performed using a drug called Mitomycin-C, an antimetabolite which blocks scar tissue from forming.

Excision with Conjunctival Autograft

The most technically challenging method is removal of the pterygium with placement of a conjunctival autograft (‘auto’ meaning from the same patient) on the defect. This tissue is harvested from the patient’s own eye, usually underneath the upper lid where the donor site can heal quickly. The conjunctival graft is either sutured in place and/or fibrin glue can be used. If sutures are used they are typically removed in the office about 2 weeks after surgery. This technique has the lowest risk of recurrence.

Beta Irradiation

More commonly used in the past, a small probe tipped with a Strontium-90 radioactive isotope was placed on the operative site to block scar tissue formation. This was generally a safe procedure but there were cases of poor wound healing leading to serious complications. The problem with beta radiation is the inability to measure exactly how much energy the surface of the eye was being exposed to. This has largely been replaced by Mitomycin-C as mentioned above.