ICD-10 Code H18.21 – Corneal edema secondary to contact lens (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H18.21 – Corneal edema secondary to contact lens
What it is
This code identifies corneal swelling caused by contact lens wear. It refers to edema of the cornea that is documented as secondary to contact lens use.
Clinical signs
Clinical features may include blurred vision, halos, eye discomfort, and corneal clouding. Clinical features vary; refer to documentation.
When to use this code
Use H18.21 when the provider documents corneal edema due to contact lens wear, fitting, or overuse. Apply it when the record clearly links the edema to contact lens use. If the cause is not stated, check documentation before coding.
Do not use for
Do not use this code for corneal edema from trauma, infection, surgery, or other non–contact lens causes. Do not assign it when contact lens involvement is only suspected or not documented.
Coding tip
Verify that the chart explicitly states “secondary to contact lens” or an equivalent causal link before assigning H18.21.