ICD-10 Code H33.12 – Parasitic cyst of retina (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H33.12 – Parasitic cyst of retina
What it is
H33.12 identifies a parasitic cyst located in the retina. Use it when documentation shows a retinal cyst caused by a parasite, not a nonspecific retinal lesion.
Clinical signs
Clinical features vary; refer to documentation. Findings may include visual disturbance, retinal abnormality on examination, or imaging evidence of a cystic retinal lesion consistent with parasitic involvement.
When to use this code
Use H33.12 when the provider documents a parasitic cyst affecting the retina and the diagnosis is established or clearly supported. It may appear in ophthalmology notes, consults, or discharge summaries. Code the condition as documented, and check laterality or associated findings if the record specifies them.
Do not use for
Do not use this code for nonparasitic retinal cysts, nonspecific retinal degeneration, or vague “retinal lesion” documentation. Check documentation if the cause is unclear or if the cyst is elsewhere in the eye.
Coding tip
Confirm that the parasite-related diagnosis is explicitly tied to the retina before assigning H33.12.