ICD-10 Code H18.4 – Corneal degeneration (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H18.4 – Corneal degeneration
What it is
H18.4 identifies degeneration of the cornea, meaning a noninflammatory breakdown or change in corneal tissue. Use it when the record documents corneal degeneration rather than infection, acute injury, or another specific corneal disorder.
Clinical signs
Findings may include corneal opacity, thinning, deposits, or surface irregularity. Clinical features vary; refer to documentation and the ophthalmology assessment for the specific degenerative pattern.
When to use this code
Use this code when the provider documents corneal degeneration, corneal dystrophic change, or similar degenerative corneal pathology without a more specific diagnosis. It may apply when the chart describes chronic corneal structural change affecting vision or corneal clarity. Check documentation if the note uses a named corneal disorder or another exact code exists.
Do not use for
Do not use H18.4 for corneal ulcer, keratitis, trauma, or postoperative complications. If the condition is better described by a specific corneal dystrophy or other eye disorder, code that diagnosis instead.
Coding tip
Choose the most specific corneal diagnosis documented; if the provider only says “degeneration,” H18.4 is appropriate.