A pterygium is a raised triangular area of eyeball conjunctiva (mucous membrane) which actively invades the corneal surface. The primary cause is sunny, hot, dusty conditions leading to tissue damage. The raised leading edge of the pterygium causes local drying, stimulating further growth of the wedge of scar tissue.
A Pingueculum is the raised solar degeneration of the conjunctiva that precedes the corneal invasion of a pterygium. Pingueculae rarely cause enough trouble to warrant their removal.
Symptoms of Pterygium that may reflect indications for surgery
Threat to the visual axis by progressive growth.
Restriction of ocular movement (usually from recurrent rather than primary pterygium).
Marked irritation, inflammation and/or cosmetic appearance.
Sunglasses to reduce the stimulus for pterygium growth.
Ocular lubricants (artificial tears) for symptomatic relief (+/- decongestant for cosmetic effect).
Quality close-up photograph highly recommended for self-monitoring of growth.
For more information please visit the link below
http://www.aao.org American Academy of Ophthalmology