Overview

• Trichiasis-when hair arising from normal skin contacts the corneal or conjunctival surfaces.
• Distichiasis-when extra lashes emerge from or near the meibomian gland orifices on the lid margin; these hairs may or may not contact the cornea.
• Ectopic cilia-single or multiple hairs that arise from the palpebral conjunctival surface several millimeters from the lid margin, most commonly near the middle of the superior lid. Occasionally ectopic cilia can arise on the back of the third eyelid.

Signalment

• Common in dog; rare in cat.
• Most common in young dogs.
• Any breed may be affected.
• Trichiasis: (a) facial fold trichiasis-common in brachycephalic breeds with prominent facial folds (e.g. Pekingese, pug and bulldog); (b) eyelid agenesis-sporadic. Usually bilateral at lateral aspect of upper lids in cats. Often associated with concurrent intraocular abnormalities; (c) entropion-conformational entropion is common in young dogs in predisposed breeds (Shar Pei, retriever, Chow Chow, among many others). Can be associated with blepharospasm (spastic entropion), scarring (cicatricial entropion), or enophthalmos; occasionally seen in cats.
• Distichiasis-predisposed breeds include cocker spaniel, American water spaniel, English bulldog, beagle, flat-coated retriever and dachshund. Dogs with distichiasis are also prone to have ectopic cilia. Rare in cats.
• Ectopic cilia-predisposed breeds include Pekingese, shih tzu and English bulldog.

Signs

Causes & Risk Factors

Usually related to facial conformation or breed predisposition, or is idiopathic.

Differential Diagnosis

• Secondary to other adnexal abnormalities (e.g., entropion, eyelid agenesis).
• Keratoconjunctivitis sicca.
• Conjunctival foreign body.
• Infectious conjunctivitis.
• Diagnosis based on direct observation of abnormal cilia and lid conformation.

CBC/Biochemistry/Urinalysis

N/A

Other Laboratory Tests

N/A

Imaging

N/A

Diagnostic Procedures

N/A

Trichiasis

• May be managed conservatively in some patients by protecting the cornea with topical lubricating ointments.
• Clipping the hair on facial folds may cause these hairs to become stiffer and more irritating.
• Surgical correction of adnexal abnormalities.
• May resect facial folds.
• Medial canthoplasty-often an effective procedure for nasal trichiasis; also eliminates lagophthalmos and medial entropion.
• Entropion repair.
• Repair of eyelid agenesis or treat distichiasis as noted below.
• Treat underlying cause (e.g., spastic entropion, enophthalmia).

Distichiasis

• Usually asymptomatic and requires no treatment.
• Symptomatic-may treat surgically by cryoepilation, electroepilation, transconjunctival electrocautery and periodic manual epilation.
• Lid-splitting and partial tarsal plate excision techniques-avoid; postoperative scarring may predispose patient to cicatricial entropion and impaired lid function.

Ectopic Cilia

• May be treated surgically-en-bloc resection of the cilia and associated meibomian gland.
• Cryotherapy-may be used as the sole treatment or as an adjunct after surgical resection.
• May develop ectopic cilia at other locations.
• Recheck patient if clinical signs recur.

Drug(s)

• Rarely indicated.
• Lubricant ointments-sometimes valuable to soften cilia and lessen irritation before surgical correction.
• Soft contact lens-sometimes can use temporarily to relieve clinical signs before surgical correction.
• Topical antibiotics-perioperative; recommended for patients undergoing surgery to minimize conjunctival flora in the surgical sites.

Contraindications/Possible Interactions

N/A