Pinguecula appears as a white-yellow lump, which may be a flat patch or slightly raised on the conjunctiva covering the sclera on the side of the cornea, also known as the “black eye”. Pterygium has its roots in the Greek language (pteryx/pterygos meaning wing). It appears as a red or pink triangular fleshy growth resembling a bird’s wing, extending from the conjunctiva with the triangular apex toward the cornea. Pterygium grows slowly and varies in size from small and atrophic to large. It may grow rapidly and have many blood vessels. In severe cases, it can extend to the center of the cornea and obstruct vision. Pterygium is a benign tumor. Both pinguecula and pterygium are not cancerous.
Pinguecula and pterygium are commonly found between the upper and lower eyelids, which are areas exposed to sunlight, more often at the nasal side than the temporal side. However, they can be found on the sclera at the nasal side, temporal side, or both locations simultaneously. Pinguecula differs from pterygium in that pinguecula does not extend onto the cornea. Both pinguecula and pterygium may become inflamed, causing symptoms such as burning, eye irritation, redness, or pain.
Symptoms of Pinguecula and Pterygium
People with pinguecula and pterygium may experience a range of symptoms, from none at all to redness, swelling, itching, irritation, burning, tearing, pain, or a sensation of a foreign body in the eye. Pinguecula can grow larger but usually does so slowly.
Generally, pinguecula and pterygium do not cause vision loss, except in severe pterygium cases that extend to the center of the cornea. This is directly related to the raised conjunctiva and the surrounding cornea. The main cause of vision reduction is the pterygium itself, which affects light refraction, induces astigmatism from the growth extending onto the cornea, blocks or clouds the visual axis, and recurrent inflammation of the pterygium that cannot be relieved by treatment with eye drops and/or topical medications. Typically, pterygium does not cause significant abnormal vision loss.
Types of Pterygium
Pterygium can be classified in various ways, such as by the location of corneal invasion, by whether the pterygium is atrophic or inflamed, or by corneal higher-order irregularities caused, among others.
Prevention and Treatment of Pinguecula and Pterygium
Mild or asymptomatic pinguecula and pterygium can be left untreated without harm, with the following recommendations:
- Avoid triggers or risk factors that cause the condition.
- Wear sunglasses outdoors to reduce UV exposure, helping to prevent pinguecula and/or pterygium. For those already affected, wearing sunglasses helps prevent progression and reduces symptoms.
- Use eye drops or lubricants, such as steroid-containing eye drops for short-term use or artificial tears, to relieve irritation and reduce redness. However, eye drops cannot cure pinguecula or pterygium.
- Surgery is usually performed when pterygium grows significantly onto the cornea, causes abnormal vision loss, or for cosmetic reasons. Mild cases do not require surgery. Pinguecula does not need to be surgically removed as it is harmless to the eye. The choice of surgical method depends on the condition of the pterygium and the patient.
