ICD-10 Code H40.06 – Primary angle closure without glaucoma damage (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H40.06 – Primary angle closure without glaucoma damage
What it is
This code identifies primary angle closure in which the drainage angle of the eye is narrowed or blocked, but there is no documented glaucomatous optic nerve damage. Use it when the condition is present before glaucoma damage is confirmed.
Clinical signs
Findings may include a shallow anterior chamber, narrow or closed angle on examination, and elevated or intermittently elevated intraocular pressure. Clinical features vary; refer to documentation.
When to use this code
Use this code when the provider documents primary angle closure and specifically states there is no glaucoma damage. It also fits cases described as angle closure without optic nerve changes or without confirmed glaucoma. If the record is unclear, check documentation before assigning the code.
Do not use for
Do not use this code when glaucoma damage is documented, since that requires a different diagnosis code. Also avoid it for secondary angle closure or other non-primary glaucoma conditions.
Coding tip
Code only when the note clearly distinguishes angle closure from glaucoma damage; if that distinction is missing, query the provider.