Pterygium is a triangular-shaped fold of the conjunctiva over the white of the eye that is going to grow across the cornea and partly also in the cornea. The fold will thereby take the form of an elongated triangular wing. If the pterygium is growing in front of the pupil, vision may be obstructed and sometimes even cause double images.


To date, a real cause has not been found. The condition is common among people who stay in the tropics for a long time. The development of a pterygium is enhanced by UV radiation. Chronic irritation of the eyes from wind, dust and dehydration also appears to be a cause.


A pterygium is usually located at the nasal side of the eye. In most cases, there are no problems. Sometimes there is a chronic irritation and the eye is red at the side of the pterygium. By growth or by a changed cornea curvature, vision can be reduced. Vision can also reduce when the pterygium grows in front of the pupil opening.


The diagnosis of a pterygium can usually be made by looking at the eye. The ophthalmologist can examine a pterygium with a slit lamp. Some dye (fluorescein) is first applied to the eye then. Next, the eye is examined with blue light. Upon dehydration of the cornea, tiny pits can be seen that illuminate in the blue light by the fluorescein. Deformation of the cornea can be measured with a keratometer.


The treatment depends on the symptoms. If there are little or no symptoms, no treatment is necessary. Anti-inflammatory eye drops can reduce the symptoms of irritation or redness. Upon dehydration of the cornea, artificial tears (in the form of drops or gel) can bring relief.
When vision is threatened, or if there are other serious problems, it can be decided to do surgery. Such an operation includes removing the pterygium and polishing the underlying cornea surface. Then a new piece of mucosa is attached to the open place that is created. For this purpose, a piece of mucosa from the patient himself is used from the same eye.


A pterygium that has to be treated, because vision is obstructed, sometimes grows back again after the treatment. A new operation may be necessary then.


For prevention:

After the operation: