ICD-10 Code H21.322 – Implantation cysts of iris, ciliary body or anterior chamber, left eye (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H21.322 – Implantation cysts of iris, ciliary body or anterior chamber, left eye
What it is
This code identifies an implantation cyst involving the iris, ciliary body, or anterior chamber in the left eye. It documents the anatomic site and laterality, not the cause or treatment.
Clinical signs
Findings may include a visible cystic lesion on eye examination or imaging. Clinical features vary; refer to documentation for size, location, and whether the lesion affects vision or ocular structures.
When to use this code
Use H21.322 when the provider documents an implantation cyst in the left eye affecting the iris, ciliary body, or anterior chamber. This is appropriate for confirmed diagnoses, postoperative or traumatic implantation cysts, and follow-up visits when the condition remains active.
Code it only when the record clearly identifies the left eye and the specific intraocular location. If the note says only “ocular cyst” or does not specify laterality, check documentation.
Do not use for
Do not use this code for cysts in the right eye, unspecified eye, or lesions outside the iris, ciliary body, or anterior chamber. Do not assign it when documentation is too vague to confirm an implantation cyst.
Coding tip
Verify both laterality and the exact intraocular site before assigning H21.322.