ICD-10 Code H21.513 – Anterior synechiae (iris), bilateral (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H21.513 – Anterior synechiae (iris), bilateral
What it is
H21.513 identifies adhesions where the iris is abnormally attached to the cornea or angle in both eyes. This code describes a bilateral anatomic finding, not a specific cause.
Clinical signs
Clinical features vary; refer to documentation. Findings may include visible iris adhesions on slit-lamp examination and possible distortion of the normal anterior chamber angle.
When to use this code
Use this code when the provider documents anterior synechiae in both eyes. It is appropriate for ophthalmology notes, exam findings, or problem lists that clearly state bilateral involvement. If laterality is not documented, check documentation before coding.
Do not use for
Do not use this code for unilateral anterior synechiae or for posterior synechiae. If the record only mentions glaucoma, cataract, or inflammation without documented synechiae, do not assume this diagnosis.
Coding tip
Confirm bilateral laterality in the assessment or exam note before assigning H21.513.