What is Pterygium?
A pterygium is a wing-shaped extension of thickened tissue on the surface (conjunctiva) of the white of the eye, which grows onto the adjacent cornea (the window into the eye). Pterygia are benign growths (not cancers), which can continue to grow across the eye and eventually seriously affect sight. It is a fairly common condition. It may occur in one or both eyes. Pterygia generally start in susceptible young adults, and gradually increase in size over the years. In some people, growth may cease after a period, and particularly in the elderly, they may become inactive.
What is the cause of pterygium?
The causes of pterygia are not clearly understood, but it is known that the ultraviolet rays present in sunlight, as well as chronic irritation due to dust etc, play a major part in their development and growth. They are more common in people between the ages of 20 and 50 years and more common in men
What are the symptoms of Pterygium?
Symptoms include recurrent redness, a feeling of irritation, and watering, although some people may not have any symptoms. If the pterygium grows too far across the cornea, it may affect sight.
What are the treatment options?
Protection from the elements (wind, dust, sea water, sunlight etc) is important; particularly the wearing of a hat and UV filtering sun-glasses, when outdoors. This will reduce symptoms, and prevent progression. It will also reduce the risk of recurrence following removal. In addition, for small pterygia which do not seem to be growing and for which surgery is not necessary, lubricant drops, and occasional decongestant drops that reduce the redness, may be prescribed. If the pterygium appears to be growing, removal is necessary before it gets to the point where it starts to affect vision. If it is left to grow too far across the cornea, residual scarring means that even after excision vision will not return to normal.
When is pterygium removal indicated?
Pterygium excision is done in following cases
- Threat to normal vision
- Induced astigmatism – the pterygium may alter the curve of the cornea
- Symptoms of irritation, redness and tearing that cannot be controlled using eye drops
- Interference with the wearing of contact lenses
- Cosmetic – some people may want to have the pterygium removed if it becomes unsightly
Is pterygium surgery similar to cataract surgery?Surgery is generally performed using local anaesthesia. Modern surgical treatment involves excision of the pterygium, and using a “graft” of adjacent conjunctiva with stem cells from the same eye to cover the bare area left by the excision on the white of the eye. This has the advantage of preventing recurrence. Following surgery, the the patient might experience watering ,redness and foreign body sensation for a few days .This is due to the surgery having been on the surface of the eye rather than within it (cataract surgery, by contrast, being fairly comfortable post operatively) and the graft is secured by sutures that are removed in a few days or are absorbable.
Can pterygium grow again?A pterygium may grow back after it has been removed. The recurrent growth is often more rapid than the growth of the initial pterygium, and each successive excision more diffi cult surgically. Recurrence following simple excision may be as high as 25%, but with modern conjunctival graft methods, is much lower.