A Pterygium is a wedge-shaped growth on the white of the eye that can progress across the pupil. Pterygia often occur in people who have spent a long time in hot, dusty countries, it's common in surfers, and in people who work outdoors. Sun exposure is one of the main causes of Pterygia. Ultraviolet light from the side of the face is thought to pass through the cornea, which acts as a side-on magnifying lens to concentrate light onto the eye and cause this non-cancerous growth. This may explain why Pterygia occur mostly at the nasal side of the eye. In the early stages, the eye may feel uncomfortable and look slightly red. Artificial tears can help reduce irritation. In most cases, Ptyergia do not interfere with vision and therefore surgical removal is not required. However, if the pterygium grows further towards the pupil, it may blur vision and it is best to consider removal.