H21.33
⚠ Non-billable (Header)Parasitic cyst of iris, ciliary body or anterior chamber
Diseases of the eye and adnexa (H00-H59)
⚠️ This is a category header code — not billable. Use a more specific child code below.
⚠️ Excludes2
inheritedRules inherited from parent codes.
Child Codes (4)
Clinical Description
ICD-10-CM code H21.33 represents parasitic cyst of iris, ciliary body or anterior chamber. This code falls under the Diseases of the eye and adnexa (H00-H59) classification. It is a non-billable category header code. A more specific child code from the list below must be used for billing and reimbursement purposes.
This is a 6-character code at the 5th level of specificity. There are 4 more specific child codes under H21.33.
Frequently Asked Questions
What is ICD-10 code H21.33?
ICD-10-CM code H21.33 is "Parasitic cyst of iris, ciliary body or anterior chamber". It belongs to the category: Diseases of the eye and adnexa (H00-H59).
Is H21.33 a billable ICD-10 code?
No, H21.33 is a non-billable header code. A more specific child code must be used for billing.
Can H21.33 be coded with other codes?
H21.33 has 2 Excludes2 note(s). These conditions can be coded together if both are documented in the patient record.
Related Codes in H21.3
Other codes in the same category that may be relevant for differential coding:
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Data Source
CMS ICD-10-CM 2026 Tabular List
Updated October 1, 2025 (FY2026)