Pterygium

Pterygium is a benign, fibrovascular growth of the bulbar conjunctiva that extends onto the peripheral cornea, usually from the nasal side. It begins as a thickening near the limbus and can grow across the corneal surface, potentially affecting vision if it encroaches on the central cornea. The exact cause is multifactorial, but ultraviolet radiation from sunlight is a major factor. Other contributors include dry eye, wind, dust, and living in sunny, arid, or tropical climates. Risk factors include outdoor work, geographic location near the equator, older age, and in some populations, male sex.

Patients may be asymptomatic or experience irritation, a gritty sensation, redness, tearing, and foreign body sensation. On examination, it appears as a triangular, fibrovascular tissue extending from the nasal conjunctiva onto the cornea. It is distinguished from a pinguecula, which does not cross the limbus.

Most small pterygia are observed if they are stable and not threatening vision. Preventive measures include ultraviolet protection (UV-blocking sunglasses, brimmed hats) and artificial tears. For symptomatic cases or progressive growth, treatment may involve lubricants and anti-inflammatory medications. Surgical removal is considered when vision is threatened by induced astigmatism or when cosmetic concerns are significant.

Modern surgery favors conjunctival autograft or amniotic membrane transplantation over bare sclera excision because these techniques reduce recurrence. Postoperative care typically includes short courses of topical steroids and antibiotics. Recurrence rates vary, with higher rates linked to bare sclera techniques and younger patients; autograft or amniotic membrane methods have lower recurrence and are generally safer. Overall prognosis with appropriate management is good, but recurrence remains a common issue. Complications are uncommon but can include scleral thinning, scarring, or infection.