ICD-10 Code H21.509 – Unspecified adhesions of iris and ciliary body, unspecified eye (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H21.509 – Unspecified adhesions of iris and ciliary body, unspecified eye
What it is
This code identifies adhesions involving the iris and ciliary body in an unspecified eye, when the chart does not specify laterality or a more precise type. Use it for documented synechiae or similar adhesions without further detail.
Clinical signs
Findings may include abnormal iris-biliary attachment noted on slit-lamp exam, distorted pupil shape, or reduced iris mobility. Clinical features vary; refer to documentation.
When to use this code
Use H21.509 when the provider documents adhesions of the iris and ciliary body but does not identify the eye or provide a more specific diagnosis. It also fits when the record confirms adhesions but leaves laterality unspecified. Check documentation if the note suggests a different anterior segment disorder.
Do not use for
Do not use this code for posterior synechiae, other specified adhesions, or conditions with a documented eye side when a laterality-specific code is available. Check documentation.
Coding tip
Confirm whether the note names the affected eye or a more specific adhesion type before defaulting to H21.509.