The problem caused by the inward growth of eyelashes toward the eye is called trichiasis. It causes the eyelashes to rub against the inner surface of the eyelids, the conjunctiva and the cornea. It's a common eyelid problem that leads to eye irritation. Trichiasis can occur due to many causes including trauma, swelling of the eyelid, eye infection and autoimmune conditions. It may also develop due to epiblepharon, chronic blepharitis, trachoma, Herpes zoster eye disease, rare skin and mucous membrane disorders, or unknown causes. Trichiasis is more common in adults but it can also affect children. Treatment involves redirecting the eyelash growth or the removal of the eyelash, follicle, or both.