ICD-10 Code H21.42 – Pupillary membranes, left eye (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H21.42 – Pupillary membranes, left eye
What it is
H21.42 identifies a pupillary membrane in the left eye. This means a residual fibrous or tissue-like membrane remains across or near the pupil and may interfere with normal light entry.
Clinical signs
Clinical features vary; refer to documentation. Findings may include a visible membrane over the pupil, partial pupillary obstruction, or associated visual disturbance noted on eye examination.
When to use this code
Use H21.42 when the record specifically documents a pupillary membrane in the left eye. This code is appropriate for congenital or acquired membrane findings when the provider identifies the left eye as affected. Check documentation if laterality is unclear or if the membrane is described only as bilateral or unspecified.
Do not use for
Do not use this code for right-eye or bilateral pupillary membranes. It is also incorrect when the chart mentions a different anterior segment disorder without a documented pupillary membrane.
Coding tip
Always verify laterality in the ophthalmology note before assigning H21.42.