Exact cause unknown

Associated with excessive exposure to wind, sunlight or sand. Therefore, it is more likely to occur in populations that inhabit the areas near the equator, as well as windy locations. The predominance of pterygia on the nasal side is possibly a result of the sun's rays passing laterally through the cornea where it undergoes refraction and becomes focused on the medial limbic area. The shadow of the nose medially reduces the intensity of sunlight focused on the lateral limbus. Pterygia are twice as likely to occur in men as in women.

As it is a benign growth, a pterygium typically does not require surgery unless it grows to such an extent that it covers the pupil, obstructing vision, or presents with acute symptoms. Some of the irritating symptoms can be addressed with artificial tears. However, no reliable medical treatment exists to reduce or even prevent pterygium progression. Definitive treatment is achieved only by surgical removal. Long-term follow-up is required as a pterygium may recur even after complete surgical correction.