What is a pterygium?
A pterygium is a membrane that grows visibly on the surface of the eye, usually from the nasal side. It can interfere with vision if it grows over the cornea (in front of the coloured iris).

What causes a pterygium?
Pterygiums are usually caused by ultraviolet light exposure (sunlight) and wind in dry conditions. It can be prevented to a large extent by wearing sunglasses, but it may also be genetic.
How is a pterygium treated?
A pterygium can only be treated by an operation in which it is removed from the surface of the eye with microscopic surgical techniques. The growth is removed, normal tissue is transplanted and fixed with tissue glue. The procedure is painless and can be performed under local or general anaesthesia, or conscious sedation.
Can a pterygium reoccur?
Yes, if the eye is still exposed to ultraviolet light or dry conditions, the pterygium may grow again over the surface of the eye. With modern surgical techniques, the recurrence rate is very low.