Pterygium is most commonly caused by exposure to which factor?

Pterygium is most commonly caused by exposure to which factor?

• A. UV light exposure
• B. Cigarette smoke
• C. Bacteria
• D. Allergic reaction

Answer: (A)

UV light exposure is the main cause. Chronic UV radiation, especially UV-B, damages the limbal area of the eye and triggers a fibrovascular proliferation from the conjunctiva that grows onto the cornea, forming a pterygium. This is more common in people with significant outdoor sun exposure, such as outdoor workers and those living near the equator. While irritation from cigarette smoke, bacteria, or allergic reactions can accompany eye problems, they do not typically initiate the characteristic tissue growth onto the cornea, making UV exposure the best explanation.

UV light exposure is the main cause. Chronic UV radiation, especially UV-B, damages the limbal area of the eye and triggers a fibrovascular proliferation from the conjunctiva that grows onto the cornea, forming a pterygium. This is more common in people with significant outdoor sun exposure, such as outdoor workers and those living near the equator. While irritation from cigarette smoke, bacteria, or allergic reactions can accompany eye problems, they do not typically initiate the characteristic tissue growth onto the cornea, making UV exposure the best explanation.