inverted eyelash

Hello! Today I saw in a bus whose eyelid was inverted and the lashes were rubbing against her eye. She was sitting next to me, and It was embarrassing to look at her. I have never seen such thing before. Does anybody know how this happens?

Hi! What you saw is actually a condition called entropion, when an eyelid turns inward. It is usually caused by scarring from trauma or inflammation from certain diseases that involve the eyelids or it may stem from a muscle spasm. When this happens, , the lashes rub against the eye, resulting in irritation, scratchiness, tearing and redness. This condition is usually corrected by surgery but some people pull the lower lid down with a piece of tape to relieve the condition temporarily.