What H20 covers · when clinicians use it
ICD-10 code H20 identifies Iridocyclitis in the U.S. ICD-10-CM clinical and billing record set. It sits within the Eye and Adnexa chapter (H00–H59), the section that groups related diagnoses so providers, payers, and public-health agencies report them consistently. Clinicians and medical coders apply H20 when an encounter's findings match the Iridocyclitis description, attaching it to the patient record so downstream insurance claims, payer audits, quality reporting, and epidemiological surveillance all reference the same standardized diagnosis. The ICD-10-CM is maintained by the Centers for Medicare & Medicaid Services and the CDC's National Center for Health Statistics, with an updated official code set released each U.S. fiscal year — always verify H20 against the current CMS/CDC release and your payer's documentation guidance before final use. This page summarizes documentation context for H20 and is a coding reference, not clinical, diagnostic, or billing advice.
H20 refers to Iridocyclitis, a set of eye conditions affecting the sclera, cornea, iris, or ciliary body. These structures are essential for protecting the eye and maintaining vision, and disorders here often lead to inflammation, scarring, or visual distortion.
Symptoms
- Eye redness and pain – Common in keratitis (H16) and scleritis (H15)
- Blurred or decreased vision – Especially in H17 corneal scars and H18 corneal dystrophies
- Photophobia – Light sensitivity in iritis and keratouveitis (H20)
- Tearing and discharge – Found in infectious keratitis or corneal ulcers
- Visible opacities or white spots – Seen in corneal scarring or degenerations
- Eye pressure sensation – Often related to inflammation of the ciliary body
- Inflammation secondary to systemic disease – Seen in H22 (e.g., from sarcoidosis or RA)
Diagnosis
Diagnosis of Iridocyclitis involves slit-lamp biomicroscopy, corneal staining, intraocular pressure measurement, anterior chamber exam, and in some cases, laboratory tests or imaging to rule out systemic inflammatory or autoimmune causes.
ICD10 Code Usage
ICD10 code H20 is used in ophthalmology, rheumatology, emergency medicine, and primary care. It assists in documentation for vision-threatening anterior segment disorders, treatment justification, surgery planning (e.g., corneal transplant), and systemic disease monitoring.
Related Codes
- H15 – Disorders of sclera
- H16 – Keratitis
- H17 – Corneal scars and opacities
- H18 – Other disorders of cornea
- H21 – Other disorders of iris and ciliary body
- H22 – Disorders of iris and ciliary body in diseases classified elsewhere
FAQs
Q1: What is ICD10 code H20?
A: It refers to Iridocyclitis, affecting the sclera, cornea, iris, or ciliary body—parts critical to vision and eye structure.
Q2: Are these conditions vision-threatening?
A: Yes, if untreated, especially keratitis, iridocyclitis, and corneal scars can cause permanent vision loss or complications.
Q3: What causes these disorders?
A: Causes include infections, trauma, autoimmune disease, surgery, or congenital conditions.
Q4: What are typical treatments?
A: Antibiotic or steroid eye drops, immunosuppressive agents, lubricants, or surgical procedures such as corneal grafting or synechiae lysis.
Q5: Who manages these disorders?
A: Ophthalmologists, corneal specialists, and systemic disease physicians like rheumatologists if associated with autoimmune disease.
Conclusion
ICD10 code H20 enables proper classification and care of Iridocyclitis, facilitating timely treatment and protecting vision through early recognition and management of anterior segment disorders.