FILAMENTARY KERATITIS

It is a type of superficial punctate keratitis, associated with formation of corneal epithelial filaments.

Pathogenesis
Corneal filaments which essentially consist of a tag of elongated epithelium are formed due to aberrant epithelial healing. Therefore, any condition that leads
to focal epithelial erosion may produce filamentary
  keratopathy.

Causes
The common conditions associated with filamentary keratopathy are:
1. Keratoconjunctivitis sicca (KCS).
2. Superior limbic keratoconjunctivitis.
3. Epitheliopathy due to radiation keratitis.
4. Following epithelial erosions as in herpes simplex keratitis, Thygeson's superficial punctate keratitis, recurrent corneal erosion syndrome and trachoma.
5. Prolonged patching of the eye particularly following ocular surgery like cataract.
6. Systemic disorders like diabetes mellitus, ectodermal dysplasia and psoriasis.
7. Idiopathic.

Clinical features

Symptoms. Patients usually experience moderate pain, ocular irritation, lacrimation and foreign body sensation.

Signs. Corneal examination reveals. 

• Filaments i.e., fine tags of elongated epithelium which are firmly attached at the base, intertwined with mucus and degenerated cells. The filament is freely movable over the cornea.
• Superficial punctate keratitis of varying degree is usually associated with corneal filaments.

Treatment
1. Management of filaments include their mechanical debridement and patching for 24 hours followed by lubricating drops.

2. Therapeutic soft contact lenses may be useful in recurrent cases.

3. Treatment of the underlying cause to prevent recurrence.