A pterygium is a fleshy growth that invades the cornea. It is an abnormal process in which the conjunctiva (the membrane that covers the white of the eye) grows into the cornea. A pterygium may or may not interfere with vision depending on its size. It commonly occurs on the inner corner of the eye. A pinguecula is a yellowish patch or bump on the conjunctiva. It too most commonly is found on the inner corner of the eye nearest to the nose. It is not a tumor, but an alteration of normal tissue resulting in a deposit of protein and fat. Unlike a pterygium, a pinguecula does not actually grow onto the cornea.
The exact cause for both pterygiums and pingueculae are not well understood. A pterygium occurs more often in people who spend a great deal of time outdoors, especially in sunny, dry climates. Long-term exposure to sunlight, ultraviolet (UV) rays, and chronic eye irritation play an important causal role. Protecting your eyes from excessive UV light with quality sunglasses and avoiding dry, dusty, windy conditions may be the best prevention.
Symptoms for both include red and irritated eyes with visibly noticeable bumps (usually involving the inner corner of the eye). If the pterygium is large enough, it may blur vision. Topical eye drops or ointments may be used to help reduce inflammation for both. If a pterygium begins to alter vision or causes persistent discomfort, surgical removal may be the best course of action.
The surgery involves the removal of the pterygium and the placement of a conjunctival patch autograft (a small piece of the patient’s own normal conjunctiva) over the area. Complications associated with pterygium surgery are unusual. Problems can occur days, weeks or even months later and may include 5-40% recurrence rate, infection, scarring, double vision and in extremely rare cases, possible loss of sight.