What is a pterygium?
A pterygium is an overgrowth of tissue from the white of the eye over onto the cornea (the crystal window of the eye). It normally presents on the ‘nose’ side of the eye although occasionally, in less than 1 percent of cases, it may come on the ‘ear’ side. Two ptergyiums are known as ‘pterygia’.
It usually presents in young patients over the age of 20 or 30 years although it has been known to occur during teenage years. This is NOT a cancer and is a localized disturbance on the surface of the eye. Usually a pterygium will remain stationary after a period of growth during which time it may extend 1, 2, 3 millimetres or more onto the cornea which is 12mm wide and covers the iris (the coloured part of the eye). Very occasionally it may grow further and cross the line of vision.
How common are ptergyia?
Pterygia of all shapes and sizes are extremely common and are estimated to occur in up to 10 percent of all Queenslanders and are probably less frequent in southern states.
What causes pterygia?
Although the exact cause is not known, an extremely strong relationship has been identified with how much sunlight one is exposed to in the first 10 years of life and also ongoing sunlight exposure after that time. It is very important to wear sunglasses to protect the eyes from UV exposure.
What is the treatment for pterygia?
Most pterygia can be left alone and just watched. Patients can do this quite adequately themselves by just looking in the mirror. It is probably useful for most patients with a pterygium to have an eye examination with their Optometrist every couple of years to check that the pterygium is not growing. In a small percentage of cases, surgery may be the appropriate to treat this condition. This is usually the case for patients in whom the vision is either affected already or may be affected by the continued growth of the pterygium. There are at least a dozen different methods of removing a pterygium. The most common is the removal of the ptergygium and filling the resultant defect on the surface of the eye with a piece of membrane (conjunctiva) taken from another place on the surface of the eye. This technique is associated with the least risk and the highest success rate in preventing a recurrence.
How to prevent the occurrence of pterygia?
Prevention is better than cure and there are strong reasons to believe that the use of adequate protection of the eyes against sunlight may reduce the rate of this disease occurring.
It is essential that children before kindergarten and primary school age should be kept out of the midday sun and if this is not possible, they should wear wide brimmed hats or bonnets, be wheeled in a stroller with an awning and wear appropriate sunglasses from a young age. When purchasing sunglasses, it is important that they meet Australian standards. This standard means that they offer protection from ultraviolet radiation. Wrap-around sunglasses are the most effective type.
Consult your Optometrist for help in selecting the most appropriate sunglasses.
