Trichiasis is an acquired condition in which the eyelashes are misdirected posteriorly toward the conjunctiva and/or the cornea. When there is contact with the conjunctiva, it produces a foreign body sensation and can also produce pain and photophobia. In all cases, excessive tearing is very common and, hence, causes blurry vision. Chronic inflammatory diseases of the eyelids and/or the conjunctiva are the major etiologic reasons for trichiasis. This includes chronic cicatricial pemphigoid, erythema multiform, chemical injury, trachoma, chronic blepharitis, and chronic allergies. Trauma and surgical procedures that involve the lid margin are also major reasons for the development of trichiasis. Patients with severe chronic trichiasis are some of the most difficult patients to manage in ophthalmology.
ICD10CM: H02.059 – Trichiasis without entropian unspecified eye, unspecified eyelid
SNOMEDCT: 60332004 – Trichiasis
Differential Diagnosis & Pitfalls
Although trichiasis is a physical finding, it is important to note associated findings and conditions that need to be addressed, such as a secondary corneal abrasion or corneal ulcer, as these are aberrant lashes from normal eyelash-bearing areas as opposed to those in distichiasis that come from the meibomian orifices.