Introduction 

Trichiasis is a common eyelid condition characterised by misdirected eyelashes that grow towards the ocular surface rather than away from it. This syndrome can be caused by a variety of conditions, such as chronic blepharitis, trauma, autoimmune illnesses, or idiopathic factors. One of the main concerns of trichiasis is that it can cause recurrent mechanical damage to the cornea, resulting in corneal abrasions and ulcers. These issues have a substantial influence on the quality of vision and, if left untreated, can lead to blindness.

Pathophysiology of trichiasis and corneal damage

Trichiasis-induced corneal damage results from continual friction between misdirected eyelashes and the corneal epithelium. The cornea is a highly innervated structure and is especially vulnerable to mechanical irritation. The continual rubbing of lashes against the cornea causes epithelial degradation, which promotes bacterial colonisation and increases the risk of infection. The damaged epithelial barrier makes the cornea prone to secondary infections, which can develop into ulcerations if not treated promptly.¹

Corneal abrasions from trichiasis

Definition and mechanism

A corneal abrasion is the loss of the cornea's superficial epithelial layer caused by trauma or mechanical stimulation. This repetitive stimulation can cause localised epithelial flaws that reveal the underlying stromal layer, eliciting an inflammatory response and discomfort.² If the abrasion continues without treatment, it can weaken the cornea's natural defence mechanisms, making it more vulnerable to infections. Furthermore, prolonged inflammation can cause repeated corneal erosions, which increases discomfort and slow healing.

Clinical presentation

Patients with corneal abrasions due to trichiasis often experience:

• Foreign body sensation
• Photophobia
• Tearing
• Eye redness
• Blurred vision (if the visual axis is involved)

Slit-lamp examination usually reveals a well-defined epithelial defect that stains favourably with fluorescein dye under cobalt blue light. Severe cases may also show conjunctival hyperaemia (where the whites of the eye appear red due to increased blood flow) and moderate anterior chamber irritation.³

Potential complications of corneal abrasions

If left untreated, corneal abrasions can result in: 

• Recurrent erosions as a result of faulty healing
• Increased vulnerability to bacterial infections
• Chronic inflammation and scarring
• Progression to corneal ulceration

Corneal ulcers from trichiasis

Definition and pathogenesis

A corneal ulcer is an open sore on the corneal surface that is usually accompanied by stromal infiltration and inflammation. Untreated corneal abrasions in trichiasis allow bacterial, fungal, or viral infections to enter and cause microbial keratitis (inflammation of the cornea). The inflammatory response caused by infection causes stromal deterioration, thinning, and, in severe cases, corneal perforation.⁴

Risk factors for ulcer formation

1. Persistent mechanical trauma: Ongoing irritation from trichiasis hinders proper healing
2. Bacterial colonisation: Typical pathogens include Staphylococcus aureus, Pseudomonas aeruginosa, and Streptococcus pneumoniae⁵
3. Dry eyes increase epithelial breakdown by compromising the tear film
4. Contact lens use increases susceptibility to infection in trichiasis patients

Clinical presentation

Patients with corneal ulcers present with:

• Severe pain and photophobia
• Significant conjunctival injection
• Purulent discharge
• A white or grey stromal infiltrate
• Hypopyon - presence of pus or white blood cells in the anterior chamber of the eye (in severe infections)

A slit-lamp examination with fluorescein staining indicates an irregular ulcerated lesion with stromal involvement. Corneal scraping for microbiological examination aids in the identification of the causal pathogen and the development of tailored therapy.⁶

Management of corneal complications in trichiasis

Treatment of corneal abrasions

Conservative management

• Lubrication: Preservative-free artificial tears reduce friction and aid in healing
• Prophylactic Antibiotics: Topical broad-spectrum antibiotics (such as erythromycin or fluoroquinolones) can help prevent subsequent infection⁷
• Eyelid Taping: Prevents lashes from contacting the cornea

Procedural interventions

• Eyelash epilation provides temporary comfort by manually removing misplaced lashes
• Cryotherapy or electrolysis: Permanent removal of abnormal follicles
•  In refractory situations, surgical correction involves adjusting the lid margin (e.g., tarsal rotation procedures)⁸

Management of corneal ulcers

Medical therapy

• Topical antibiotics for bacterial ulcers include fortified fluoroquinolones (such as moxifloxacin) or a combination of cephalosporins and aminoglycosides
• Antifungal or antiviral agents are based on microbiological results
•  Cycloplegics: Reduce ciliary spasm and discomfort using atropine drops
•  Anti-inflammatory Therapy: Use corticosteroids with caution and under the guidance of an ophthalmologist⁹

Surgical interventions

•  Debridement is the removal of necrotic tissue to allow medication penetration
• Amniotic Membrane Transplantation: Helps treat refractory ulcers
• Penetrating Keratoplasty (Corneal Transplantation) is used to treat vision-threatening lesions with perforated corneas¹⁰

Prevention and prognosis 

Early detection and treatment of trichiasis are critical in avoiding corneal problems. Routine eye tests, particularly in high-risk people (e.g., those with persistent blepharitis or Stevens-Johnson syndrome), can detect trichiasis before it causes major damage. The prognosis for corneal abrasions is excellent with proper treatment, with complete healing within a few days. However, corneal ulcers require immediate and urgent treatment to avoid consequences, including scarring, astigmatism, or blindness. Patients with recurrent trichiasis may benefit from definitive surgical treatment to avoid long-term complications.¹¹

Conclusion

Trichiasis is a potentially sight-threatening illness because it can cause continual corneal damage, resulting in abrasions and ulcers. Corneal abrasions, if left untreated, serve as a pathway for microbial infection, accelerating the risk of corneal ulceration and loss of vision. Management consists of a combination of medical medication and surgical procedures aimed at eliminating abnormal lashes, improving corneal healing, and preventing recurrence. Early detection and treatment strategies are critical in preventing this illness.