Trichiasis is most often idiopathic, but known causes include blepharitis Blepharitis Blepharitis is inflammation of the eyelid margins that may be acute or chronic. Symptoms and signs include itching and burning of the eyelid margins with redness and edema. Diagnosis is by history... read more , posttraumatic and postsurgical changes, conjunctival scarring (eg, secondary to cicatricial pemphigoid, atopic keratoconjunctivitis, Stevens-Johnson syndrome, or chemical injury), epiblepharon (an extra lower eyelid skinfold that directs lashes into a vertical position), and distichiasis (a congenital extra row of eyelashes).
Corneal ulceration and scarring can occur in chronic cases. Symptoms are foreign body sensation, tearing, and red eye.
Diagnosis is usually clinical. Trichiasis differs from entropion Entropion and Ectropion Entropion is inversion of an eyelid. Ectropion is eversion of the lower eyelid. This photo shows entropion, inversion of the eyelid that most commonly affects the lower eyelids of older adults... read more in that the eyelid position is normal. Evaluation includes fluorescein staining to exclude corneal abrasion or ulceration.
Treatment is eyelash removal with forceps. If eyelashes grow back, which is a frequent occurrence, electrolysis or cryosurgery is more effective at permanently preventing recurrence.