A bruise on the eye, also known as a pterygium, is a very common eye condition that generally presents as a fleshy growth in the nasal or temporal corner of the eye. The cause of this condition is not well understood, but is generally considered to be related to long-term outdoor work, sand irritation, or UV exposure. If the symptoms are mild or if the pterygium is small, it does not need to be treated. When the pterygium becomes larger and invades the cornea, causing vision loss, surgery may be considered. The most common surgical procedure is pterygium excision combined with autologous corneal limbal stem cell transplantation, which has the greatest advantage of reducing the recurrence rate of the disease and is therefore the most commonly used method.