ICD-10 Code H40.129 – Low-tension glaucoma, unspecified eye (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H40.129 – Low-tension glaucoma, unspecified eye
What it is
This code identifies low-tension glaucoma, a form of glaucoma in which optic nerve damage and visual field loss occur despite eye pressure that is not elevated. “Unspecified eye” means the documentation does not name the right, left, or both eyes.
Clinical signs
Typical findings include optic nerve cupping, corresponding visual field defects, and a glaucoma diagnosis with normal or not markedly elevated intraocular pressure. Clinical features vary; refer to documentation.
When to use this code
Use H40.129 when the provider documents low-tension or normal-tension glaucoma but does not specify the affected eye. It also fits follow-up visits for established disease when laterality is still not stated in the record. If the note names a right, left, or bilateral eye, choose the more specific code.
Do not use for
Do not use this code for ocular hypertension, glaucoma suspect, or other glaucoma types without documented low-tension glaucoma. Check documentation if the record only says “glaucoma” without laterality or subtype.
Coding tip
Assign the unspecified-eye code only when laterality truly is missing; otherwise, code the documented eye for greater specificity.