A pinguecula is a raised yellowish white mass within the bulbar conjunctiva, adjacent to the cornea. It does not tend to grow onto the cornea. However, it may cause irritation or cosmetic blemish and, although rarely necessary, can easily be removed.
A pterygium is a fleshy triangular growth of bulbar conjunctiva that may spread across and distort the cornea, induce astigmatism, and change the refractive power of the eye. Symptoms may include decreased vision and foreign body sensation. It is more common in sunny, hot, dry climates. To relieve symptoms caused by a pterygium, artificial tears or a short period of treatment with corticosteroid drops or ointments may be prescribed. Removal is often indicated for documented growth, cosmesis, to reduce irritation, and to improve or preserve vision. The technique with the best results to prevent recurrence is surgical removal of the pterygium followed by conjunctival autograft and perhaps with cyclosporine drops.