What is the most common cause of Filamentary Keratopathy?

• A. Keratoconjunctivitis sicca
• B. Bacterial keratitis
• C. Exposure keratopathy
• D. Herpes keratitis

Answer: (A)

Filamentary keratopathy arises when the tear film is unstable and the surface becomes desiccated. In dry eye conditions, there is insufficient lubrication, leading to shedding of epithelial cells and accumulation of mucous strands that form thin filaments adherent to the cornea. These filaments irritate the surface and are often seen in patients with keratoconjunctivitis sicca. Treating the underlying dry eye—by improving tear production, lubrication, or lid hygiene—helps resolve the filaments. While bacterial keratitis, herpes keratitis, and exposure keratopathy can affect the cornea in other ways, they are not the most common underlying cause of filamentary keratopathy; dry eye remains the typical precursor.