Overview

Trichiasis is an eye condition where the eyelashes grow inward toward the eye, rather than outwards. The condition typically affects the lower eyelid, even though the eyelash follicles are healthy. The misdirected eyelashes rub against the cornea, the conjunctiva, and inside the eyelids, causing irritation, discomfort, and redness. In severe cases, the condition may lead to corneal damage (the outermost layer of the eye) and can even progress to blindness if left untreated. As per statistics from 2016, 2.8 million people worldwide are currently living with trichiasis. Although the exact cause of trichiasis is unknown, certain conditions such as infection, inflammation, ageing, or trauma contribute to trichiasis.^1,2,3 Understanding the cause and associated risk factors is essential for early detection and treatment.

What are the symptoms of trichiasis?

Common trichiasis symptoms include:

• Eye redness
• Eye irritation or feeling like a foreign object in the eye
• Eye watering or tearing 
• Photophobia
• Eye discomfort^2,3

What are the risk factors involved in the development of trichiasis?

Age-related changes

Trichiasis is more common in females, and the risk increases with aging. As people age, the muscles and tendons that support eyelids weaken, leading to loss of strength and elasticity. This causes eyelashes to grow inward and rub against the eye’s surface, causing discomfort.^4,5

Chronic eye infections

Trachoma

The bacterial infection is caused by Chlamydia trachomatis. In the initial stages (5-12 days) after bacterium exposure, trachoma causes conjunctivitis. As the infection progresses, it can cause eye pain and blurred vision. If left untreated, trachoma can lead to trichiasis. 

Herpes zoster eye disease

The viral infection is caused by the reactivation of the varicella-zoster virus, leading to painful rashes on the forehead, temple, and area around the eye. The infection can cause inflammation and damage to the eyelid where the eyelashes grow, and lead to trichiasis.

Autoimmune and inflammatory conditions

Certain autoimmune and inflammatory conditions can damage the eyelids and conjunctiva, causing scarring and leading to eyelash misdirection. When the eyelid tissue heals with scar formation, it can pull the eyelashes inward, causing trichiasis. The conditions include:

Blepharitis

The condition is caused by the overpopulation of microscopic mites, known as Demodex, that live in the eyelash follicles. Chronic blepharitis causes structural changes in the eyelid, such as thickening of the lid edge, leading to trichiasis.

Stevens-Johnson syndrome

This condition develops rashes on the mouth, nose, eyes, and genitals, leading to eye inflammation.

Ocular cicatricial pemphigoid

This is a rare, chronic autoimmune disorder that affects the conjunctiva, causing scarring and inflammation. Over time, this scarring gradually damages the conjunctiva, leading to serious eye complications.

Atopic keratoconjunctivitis

This is a severe, chronic inflammatory condition typically seen in individuals with a history of atopic dermatitis. It affects both the cornea and the conjunctiva, leading to eye complications if left untreated.

Cicatrising conjunctivitis

It is a type of conjunctivitis that causes the conjunctiva to become progressively scarred, leading to eyelid deformities, irritation, and vision loss if left untreated.

Previous eye trauma or surgeries

Eyelid trauma

Previous injuries to the eyelid can disrupt the normal growth of eyelashes. Any chemical or thermal burns to the eye can also damage the eyelid margin and affect eyelash growth.^3,6

Eyelid surgery

Certain eyelid surgeries may unintentionally disturb the eyelid structure and affect eyelash growth.^3,7

Genetic and congenital factors

Genetic variations increase the risk of developing trichiasis. Children born with congenital conditions like epiblepharon can have extra skin on the lower eyelid, pushing the eyelashes upward, leading to trichiasis. Epiblepharon condition is commonly seen in Asian or Hispanic children and often resolves as the child grows older.^3,8

Environmental and lifestyle factors

Contact lens overuse

Overuse of contact lenses causes irritation or abrasion of the eye or eyelid, leading to eyelash misdirection.^3,9

Poor eye hygiene

Not cleaning eyelids regularly or improper lens care can increase the risk and lead to scarring.³

Exposure to irritants

Long-term exposure to dust, smoke, or pollutants may contribute to chronic irritation and inflammation of the eyelids.³

Tumours and growth-related factors

Eyelid tumors 

Eyelid tumors, whether benign or malignant, can damage the eyelids and cause scarring, leading to the misdirection of eyelashes.³

Chalazia

A chalazion is a painless bump that occurs when a meibomian gland in the eyelid becomes blocked. However, if left untreated or after surgical drainage, it can cause structural changes to the eyelid, leading to the misdirection of eyelashes.³

Medications

Certain medications used to treat ophthalmic conditions, such as glaucoma and eye viral infections, may contribute to eyelash changes, leading to misdirection of eyelashes. The medications include:

• Travaprost
• Pilocarpine
• Epinephrine
• Trifluridine
• Idoxuridine
• Vidarabine¹⁰

What are the preventive measures for trichiasis?

Genetic factors contributing to trichiasis cannot be prevented, but below preventive strategies might help to minimise the risk of trichiasis:

• Regularly cleaning the eyelids reduces the risk of infections and irritation that can contribute to trichiasis
• Promptly undergo treatment for underlying eye conditions such as blepharitis, conjunctivitis, and other eyelid inflammations to avoid further complications
• Protecting the eye from physical, chemical, or thermal injuries during activities that have the risk of injury
• Regular eye checkups can help detect early signs of eyelash misdirection before complications arise
• Promptly seeking medical attention or an eye care professional when suspecting the symptoms of eye irritation or discomfort¹¹

FAQs

What are the early signs of trichiasis?

The early signs of trichiasis include redness, irritation, and a sensation of something in the eye. Other symptoms include increased tearing, eye pain, blurred vision, eyelid swelling, and eye discharge.

Is trichiasis a permanent condition?

No, trichiasis is not a permanent condition. But if left untreated, it can lead to permanent damage to the cornea and lead to vision loss. With prompt treatment, it can be managed effectively.

Can children develop trichiasis?

Yes, children can develop trichiasis. Certain genetic conditions, like epiblepharon, can sometimes lead to trichiasis in children. But in most children, eyelashes will naturally outgrow as their facial bones, skin, and muscles grow.

How can I prevent trichiasis?

It is not possible to stop developing trichiasis as we cannot control eyelash growth. However, maintaining good eye hygiene, protecting eyes from injuries, and seeking prompt treatment for eye conditions can reduce the risk of developing trichiasis.

Is trichiasis contagious?

No, trichiasis is not contagious, but the infections that can cause it are. For example, trachoma, which leads to trichiasis, is contagious because the bacterium spreads very easily through direct contact with an infected individual’s eyes, eyelids, nose, or throat secretions or by handling infected items.

Summary

Trichiasis is an eye condition where the eyelashes grow toward the eye even when the eyelash follicle is healthy. Several factors, such as advancing age, infections, autoimmune conditions, trauma, and environmental factors, can contribute to misdirected eyelash growth, leading to eye irritation. Understanding these risk factors is essential for early diagnosis and timely treatment. If left untreated, trichiasis can cause complications such as corneal damage, vision loss, or permanent blindness. Preventive measures, such as maintaining good eye hygiene, avoiding environmental irritants, and scheduling regular eye check-ups, can reduce the risk of developing trichiasis. If you experience persistent discomfort or irritation, seek medical attention promptly to prevent further damage.