Recurrent pterygium of eye (Q84952)

This refers to the recurrent benign growth of the conjunctiva. A pterygium commonly grows from the nasal side of the sclera. It is usually present in the palpebral fissure. It is associated with and thought to be caused by ultraviolet-light exposure (e.g., sunlight), low humidity, and dust. 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 limbic area.