ICD-10 Code H40.212 – Acute angle-closure glaucoma, left eye (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H40.212 – Acute angle-closure glaucoma, left eye
What it is
H40.212 identifies acute angle-closure glaucoma in the left eye. It is a sudden rise in intraocular pressure caused by blocked aqueous outflow, requiring prompt recognition in the left eye.
Clinical signs
Typical findings include sudden eye pain, redness, blurred vision, halos around lights, headache, nausea, and a mid-dilated pupil. Clinical features vary; refer to documentation.
When to use this code
Use H40.212 when the provider documents acute angle-closure glaucoma affecting the left eye specifically. Apply it for confirmed acute attacks or clearly documented acute angle closure in that eye. If laterality is not stated, check documentation before coding.
Do not use for
Do not use this code for chronic glaucoma, unspecified glaucoma, or angle-closure disease without an acute attack. If the record does not confirm left-eye involvement, check documentation.
Coding tip
Always verify laterality and acuity in the provider note before assigning H40.212.