A pterygium is a wing shaped, vascular, fleshy growth that originates on the conjunctiva and can spread to the corneal limbus and beyond. It may slowly grow but rarely grows so large that the pupil is covered. Early in the disease process, pterygia are usually asymptomatic; however, there can be signs of dry eye (such as burning, itching or tearing) as the lesion causes irregular wetting of the ocular surface.