Filamentary keratopathy: A non-contact photomicrographic in vivo study in the human cornea

PURPOSE. To investigate in vivo morphology of corneal filaments. MATERIALS AND METHODS. Over a 12-year period, 19 patients with corneal filaments (7 with keratoconjunctivitis sicca and 12 with other surface diseases) were examined with the slit lamp and photographed by non-contact photomicrography. RESULTS. The filaments appeared as variously long and thick threads, attached at one or both ends to the surface and carrying various amounts of granular and amorphous material. The attachment points and their surroundings showed abnormal cells and diffusion of tear fluid stained green with fluorescein sodium. The underlying stroma appeared normal. The remaining epithelium often showed abnormal surface cells and/or edematous or cystic changes. CONCLUSIONS. The in vivo morphology of filamentary keratopathy is consistent with aggregations of mucus and cell debris adhering to the corneal surface. The underlying diseases seem to have in common corneal epithelial edema. The nature of additional factors, or their combination, precipitating mucus adherence to the surface is not clear.