Trichiasis : Information

Introduction : Trichiasis

Trichiasis is an acquired condition characterised by posterior misdirection of previously normal eye lashes. The misdirected lashes may be diffuse involving the entire lid (diffuse trichiasis) or may involve a small segment of it (simple trichiasis). Simple trichiasis is relatively more common as compared to diffuse trichiasis.

Trichiasis is differentiated from pseudotrichiasis which occurs secondary to entropion (inward turning of eyelid). Both these conditions lead to irritation of cornea and may lead to punctate epitheliopathy. Trichiasis may lead to infectious keratitis, pannus formation or even corneal ulceration.

Trichiasis may be associated with conditions like trachoma or severe chronic staphylococcal blepharitis.


References:

http://emedicine.medscape.com/article/1213321-overview

http://www.geteyesmart.org/eyesmart/diseases/trichiasis.cfm

http://vaeyecenter.com/caring-for-your-eyes/common-eye-diseases/trichiasis/

Saxena S, Clinical Ophthalmology: Medical and Surgical Approach, 2nd ed. Jaypee-Highlights, 2011, New Delhi

Basak Samar K, Atlas of Clinical Ophthalmology, 2nd ed. Jaypee Brothers Medical Publishers (P) Ltd, 2013, New Delhi, P. 6

Kanski,Jack J. Clinical Ophthalmology, A Systematic Approach .Third Edition.UK. Butterworth Heinemann, 1994.P 13-14.

Symptoms : Trichiasis

Patient may present with symptoms like:

- Irritation of eyes.

- Foreign body sensation in eye.

- Redness of eyes.

- Watering.

- Eye discharge.

- Pain in eyes.

- Increased sensitivity to light.

- Corneal abrasion.

- Corneal ulceration.

- Symblepharon (adhesion of eyelids to the eyeball).

- Loss of normal eyelid margin structures e.g. madarosis (absence or loss of eye lashes).

- Dryness of eyes due to keratinisation.

Causes : Trichiasis

There are various causes of trichiasis:-

Infectious causes:

- Trachoma.

- Herpes zoster.

Autoimmune:

- Ocular cicatricial pemphigoid.

Inflammatory:

- Stevens-Johnson syndrome

- Vernal keratoconjunctivitis.

- Chronic staphylococcal blepharitis.

Chemical:

- Alkali burns.

- Use of glaucoma eye drops.

Trauma:

- Repair of orbital floor fracture.

- Blepharoplasty (eyelid surgery).

- Repair of ectropion.

- Following enucleation.

Thermal burns to the lids:

Diagnosis : Trichiasis

Diagnosis is based on history and clinical examination.

History:

History of following conditions may be elaborated for the diagnosis:-

- Eye infections like trachoma or herpes zoster.

- Trauma or surgery of the lids.

- Chemical or thermal burns.

- Use of glaucoma eye drops.

- Inflammatory conditions like Stevens-Johnson syndrome or chronic blepharitis.

- Ocular cicatricial pemphigoid.

Clinical features:

Clinical examination helps in finding the cause of trichiasis.

Examination may require slit-lamp examination by a qualified eye-specialist.

- Trachoma: Trachoma may cause posterior lamellar (tarsus and conjunctiva) scarring. Scarring causes difficulty in eversion of eyelid.

- Stevens-Johnson syndrome and ocular cicatricial pemphigoid: These conditions lead to symblepharon formation and fornix (junction of eyelid and eyeball conjunctiva) scars.

- Involutional entropion with horizontal lid laxity: Horizontal lid laxity may be tested by snap back test. Examiner pulls lower lid down and observes the lid returning to its original position without allowing patient to blink. Normally, lid returns back quickly without blinking, but in increased laxity, blink may be needed for its return to normal position. The examiner can also pull the lower lid anteriorly away from the globe. In involutional entropion, lid may be pulled away by 6-15mm from the globe, as compared to 2-3mm only in normal lid.

Trichiasis should be differentiated from conditions like:-

- Congenital distichiasis: In congenital distichiasis, there is partial or complete second row of eye lashes growing out of or slightly behind the meibomian gland orifices. Eye lashes in this condition are thinner, shorter and less pigmented than normal cilia (eye lashes).

- Acquired metaplastic eye lashes: Acquired metaplastic eye lashes may occur in late stages of Stevens-Johnson syndrome, trachoma and chemical burns. In this, eye lashes exit near the meibomian gland orifices and are associated with other changes such as keratinisation of the conjunctiva.

- Congenital epiblepharon: Congenital epiblepharon shows an extra horizontal fold of skin which stretches across the lid margin. The eye lashes may be turned upward, particularly medially. These may touch the cornea but they rarely cause discomfort in the eye. In epiblepharon, on pulling the lid down, the lashes turn out and the normal position of lid margin becomes visible.

- Entropion: Entropion causes inversion of eyelid margin and pseudotrichiasis. Eyelash produces irritation to the exposed surface of the eyeball. In congenital entropion, on pulling the lid down, the entire eyelid is pulled away from the eyeball, unlike congenital epiblepharon.

Management : Trichiasis

Management should be carried out under medical supervision.

Management of trichiasis is primarily surgical.

Medical therapy:

- Artificial tears and ointments: Lubricating artificial tears and ointments may decrease the irritant effect of eyelash rubbing against the eyeball.

Diseases like ocular cicatricial pemphigoid and Stevens-Johnson syndrome require medical therapy of the disease, in addition to treatment of trichiasis.

Surgical therapy:

- Epilation: Epilation involves mechanical removal of eyelashes with forceps.

- Electrolysis: Eyelash follicle is destroyed by passage of electric current through a fine needle inserted into lash root.

- Cryotherapy: Cryoprobe freezes the lash follicles and destroys it. It should be avoided in cases with ocular cicatricial pemphigoid.

- Laser thermoablation: Laser thermoablation may be used to destroy eyelash follicles.

- Radiofrequency ablation: Smallest gauge wire is introduced alongside the lash to the follicle for destruction with radiofrequency.

Medical Condition : Trichiasis : Eye Ear