Filamentary keratitis, unspecified eye

This code describes a condition characterized by the presence of fine, thread-like strands (filaments) composed of epithelial cells and mucus adhering to the corneal surface. These filaments can cause foreign body sensation, pain, tearing, and photophobia. It indicates that the specific eye affected (right or left) was not documented.

Use this code when the medical record clearly documents a diagnosis of filamentary keratitis, but the physician's notes do not specify whether it affects the right or left eye. This diagnosis is typically made via slit-lamp examination. Documentation should describe the presence of corneal filaments.

• Avoid using this code if the laterality (right or left eye) is specified in the medical record; instead, use the more specific codes for right (H16.121) or left (H16.122) eye.
• Ensure the documentation supports the diagnosis of filamentary keratitis, distinguishing it from other forms of keratitis.
• Consider co-occurring conditions such as dry eye syndrome (H04.12-) or recurrent corneal erosions (H16.2-) which may contribute to filament formation.