Conditions: Trichiasis
Trichiasis is a condition in which eyelashes grow inward and rub against the eye. It can follow eyelid or periocular surgery, injury, or other causes of eyelid scarring.
What is trichiasis?
Trichiasis is a condition in which one or more eyelashes grow in the wrong direction, turning inward toward the eye instead of outward. These misdirected lashes rub against the surface of the eye, including the clear front window called the cornea and the white part called the conjunctiva. Even a single misdirected lash can cause significant irritation and, over time, damage to the eye.
Trichiasis is different from entropion, although the two often occur together. In entropion, the entire edge of the eyelid rolls inward, carrying the eyelashes with it. In trichiasis, the eyelid may sit in its normal position, but individual lashes are pointed the wrong way. Both conditions bring the lashes into harmful contact with the eye.
Causes
Trichiasis has many possible causes. In many parts of the world the most common cause is trachoma, a chronic eye infection that leads to scarring of the inner eyelid. However, trichiasis frequently develops from other conditions, including:
Eyelid or periocular surgery. Procedures on the eyelids or the area around the eye can change the way the lid heals. Scar tissue that forms during healing may pull or rotate the lash-bearing edge of the eyelid inward. For example, trichiasis is a recognized complication after eyelid reconstruction, such as a Hughes flap used to repair the lower eyelid after skin cancer removal, and after surgery to correct entropion.
Injury to the eyelid. Cuts, burns (including chemical burns), and other trauma to the eyelid can heal with scarring that redirects the eyelashes toward the eye.
Chronic inflammation and scarring conditions. Long-standing inflammation of the eyelid margin (blepharitis), and scarring diseases such as Stevens-Johnson syndrome and ocular pemphigoid, can distort the lash follicles.
Aging changes of the eyelid tissues.
In all of these situations, the underlying problem is usually scarring or contraction of the eyelid tissue that changes the direction in which the lashes grow.
Symptoms and complications
Because the misdirected lashes constantly rub the surface of the eye, common symptoms include:
A gritty, scratchy, or foreign-body sensation, as though something is in the eye
Eye pain or discomfort
Redness
Tearing or watery eyes
Sensitivity to light
A tendency to squint or keep the eye closed
Blurred vision
If trichiasis is not treated, the ongoing rubbing can scratch the cornea and lead to more serious problems. Repeated abrasion can cause corneal scarring, ulcers, and secondary infection. Over time, this damage can cloud the cornea and permanently reduce vision, and in severe cases can lead to blindness. Because of this risk, persistent inward-growing lashes are generally evaluated by an eye care professional.
How trichiasis is evaluated
An eye doctor diagnoses trichiasis through a careful examination, usually with magnification such as a slit lamp microscope. The evaluation typically includes:
Checking vision in each eye
Inspecting the eyelids to identify which lashes are misdirected and whether the eyelid margin is rolled inward (entropion)
Examining the cornea and conjunctiva for scratches, scarring, or other damage, often using a special dye that highlights areas of surface injury
Reviewing the history of any previous eye infections, eyelid surgery, or injury that may explain the condition
This assessment helps determine how many lashes are involved, how much damage has occurred, and which treatment approach is most appropriate.
Treatment options
Treatment aims to relieve discomfort and protect the eye from further damage. The choice depends on how many lashes are involved, the underlying cause, and whether the eyelid position itself is abnormal.
Epilation (plucking). Removing the offending lashes with fine forceps gives quick relief and is simple and inexpensive. However, the lashes usually grow back within several weeks, and the regrowing lashes can sometimes be stubbly and even more irritating, so this is generally a temporary measure.
Lash follicle destruction. When only a few lashes are involved, the individual lash follicles can be permanently destroyed to prevent regrowth. Methods include electrolysis (a fine needle delivering an electric current to the lash root), cryotherapy (freezing the follicles), and laser treatment. More than one session is sometimes needed.
Eyelid surgery. When many lashes are involved, when the eyelid margin is turned inward (entropion), or when other treatments have failed, surgery to reposition the eyelid and rotate the lashes away from the eye is often the most effective and durable option. Several techniques are available, and in cases caused by significant scarring, tissue grafts may be used to rebuild and reposition the eyelid margin.
Because trichiasis can recur, particularly when it results from ongoing scarring, follow-up after treatment is commonly part of care. Return of a foreign-body sensation, pain, redness, or new lashes touching the eye generally prompts re-evaluation.
Key points
Trichiasis means eyelashes grow inward and rub against the eye, causing irritation and potential damage.
It can develop after eyelid or periocular surgery or injury, when scar tissue redirects the lashes.
Left untreated, it can scar the cornea and threaten vision.
Effective treatments range from plucking and follicle destruction to eyelid surgery, chosen according to severity and cause.