ICD-10 Code H21.261 – Iris atrophy (essential) (progressive), right eye (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H21.261 – Iris atrophy (essential) (progressive), right eye
What it is
H21.261 identifies progressive, essential atrophy of the iris in the right eye. Use it when documentation specifies a degenerative iris thinning or loss of tissue, limited to the right eye.
Clinical signs
Clinical features vary; refer to documentation. Typical findings may include visible thinning of the iris, transillumination defects, or irregular iris architecture noted on eye examination.
When to use this code
Use this code when the provider documents iris atrophy as essential or progressive and clearly states the right eye. It is appropriate for ophthalmology notes, problem lists, or assessments that identify the condition without another primary cause. If the laterality is not documented, check documentation before assigning a unilateral code.
Do not use for
Do not use this code for iris changes due to trauma, surgery, inflammation, or another specified disorder. If the record does not confirm right-eye involvement or the diagnosis is uncertain, check documentation.
Coding tip
Confirm both the diagnosis wording and laterality in the ophthalmology note before coding H21.261.