A pterygium is a wedge shaped growth of abnormal tissue, usually midway between the top and bottom eyelid, on the white of the eye. 90% of them are on the side of the eye near the nose. They are not cancerous and may grow to invade and grow over the clear cornea obscuring the iris.
It’s thought that chronic exposure to environmental elements and ultra violet light causes damage to the tissue of the conjunctiva causing thickening and scarring of the tissue containing blood vessels. There is a strong correlation between pterygia and ultraviolet light, dusty environments, and not wearing sunglasses or a hat.
People who spend a lot of time outdoors are most likely; sailors and skiers are particularly at risk where there is a lot of reflected ultraviolet light. People living in places where there is depletion of the ozone layer are also more likely. People who work in dusty or dry environments are more likely to get pterygia, which is why it might be more common in men.
Pterygia occur might grow in one or both eyes and at may have different growth rates. They can be progressive and grow over the edge of the cornea. These invasive pterygia tend to be associated with other symptoms including visual distortions but they can stop growing and become quiescent, and remain this way.
A fleshy pink growth on the white at the side of the eye and can sometimes be seen to extend onto the clear cornea. Initially symptoms of irritation, dryness and scratchiness associated with inflammation and redness. These may be more frequent during the summer months, in air conditioning or a dry environment such as in front of a heater. Vision may become distorted once the pterygium involves the cornea because as it grows it may obstruct or distort vision. Pterygia commonly cause astigmatism.
Protection from the environment and ultraviolet light by wearing sunglasses and a hat will slow their development and progression. The symptoms can be alleviated by using of lubricating drops such as Tears Plus or a short course of decongestants like Albalon or Naphcon. Prescription non-steroidal anti-inflammatory drops help in more stubborn cases. Steroid eye drops are occasionally used in cases of marked inflammation but surgery may be indicated when symptoms are ongoing and chronic or vision is severely affected.