ICD-10 Code H16.121 – Filamentary keratitis, right eye (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H16.121 – Filamentary keratitis, right eye
What it is
H16.121 identifies filamentary keratitis affecting the right eye. This code is used when the corneal surface has filament formation documented in the right eye.
Clinical signs
Typical findings include corneal filaments attached to the ocular surface, eye irritation, foreign-body sensation, tearing, and discomfort. Clinical features vary; refer to documentation.
When to use this code
Use this code when the provider documents filamentary keratitis specifically in the right eye. It may apply in ophthalmology notes, consultation reports, or problem lists when laterality is clearly stated. Check documentation if the record only says keratitis without filaments or eye laterality.
Do not use for
Do not use H16.121 for keratitis without filament formation or when the condition is documented in the left eye or both eyes. Do not assign it if the record is unclear; check documentation.
Coding tip
Confirm both the filamentary keratitis diagnosis and the right-eye laterality before coding.