What Is Pseudopterygium?

Mechanism: Adhesion via Injury

The formation of a pseudopterygium is always triggered by an inflammatory event or trauma that compromises the corneal surface. Common causes include:

Chemical Burns - Alkali or acid splashes that strip the corneal epithelium.

Corneal Ulcers - Severe infections that create a "divot" in the eye surface.

Physical Trauma - Abrasions or surgeries that leave raw tissue exposed. The bulbar conjunctiva essentially acts as a biological bandage, adhering to the site of the injury to help the eye seal itself. Unlike a true pterygium, a pseudopterygium can occur at any point around the 360-degree circumference of the cornea.

The Probe Test: Differentiation

The most important clinical distinction between a true and false pterygium is the "Probe Test." Because a true pterygium grows into the layers of the cornea, it is attached along its entire length. In contrast, a pseudopterygium is often only attached at its "head" (the site of the scar). A doctor can often pass a fine surgical probe underneath the neck of a pseudopterygium without meeting resistance. This "bridge" effect is a hallmark sign that the tissue is an adhesion rather than a growth.

Visual and Physical Impact

While a pseudopterygium does not "grow" across the eye like a tumor, it can still cause significant issues. If the scar is large, it can pull on the cornea, inducing irregular astigmatism and blurring the vision. Furthermore, the raised tissue can interfere with the normal tear film, causing localized dry eye and a constant "foreign body" sensation. Because it is a scar, it may also contain small blood vessels that make the eye appear chronically red in the affected area.

Surgical Management

Treatment is not always necessary if the vision is clear and the eye is comfortable. However, if the adhesion is causing significant astigmatism or cosmetic distress, it can be surgically removed. The surgeon carefully dissects the conjunctiva away from the cornea and polishes the underlying scar. To prevent the tissue from re-attaching, a "conjunctival autograft"?taking a small piece of healthy tissue from elsewhere in the eye?is often used to cover the raw area.