ICD-10 Code H18.599 – Other hereditary corneal dystrophies, unspecified eye (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H18.599 – Other hereditary corneal dystrophies, unspecified eye
What it is
This code identifies a hereditary corneal dystrophy affecting an unspecified eye when the exact dystrophy type is not named. Use it for inherited, usually bilateral corneal disorders that are not classified elsewhere.
Clinical signs
Clinical features vary; refer to documentation. Common findings may include progressive corneal opacity, recurrent visual disturbance, glare, or reduced vision consistent with a dystrophic corneal process.
When to use this code
Use H18.599 when the provider documents a hereditary corneal dystrophy but does not specify the exact subtype, and the affected eye is not identified. It also fits cases where the record confirms a corneal dystrophy of inherited origin, but details are incomplete. Check documentation if laterality or subtype is clarified.
Do not use for
Do not use this code for acquired corneal disease, traumatic corneal scarring, or nonhereditary dystrophies. If the chart names a specific hereditary corneal dystrophy, code the specified condition instead.
Coding tip
Verify whether the note documents laterality or a more specific dystrophy before assigning this unspecified code.