ICD-10 Code H18.222 – Idiopathic corneal edema, left eye (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H18.222 – Idiopathic corneal edema, left eye
What it is
This code identifies unexplained swelling of the cornea in the left eye. It tells you the edema is idiopathic, meaning no specific cause has been documented.
Clinical signs
Typical findings include corneal haze, thickening, and reduced visual clarity in the left eye. Clinical features vary; refer to documentation for the documented exam findings or ophthalmology assessment.
When to use this code
Use H18.222 when the provider documents idiopathic corneal edema limited to the left eye. It is appropriate when the record does not identify trauma, infection, surgery, or another cause. If the cause is known or later clarified, check documentation before coding.
Do not use for
Do not use this code for corneal edema with a documented underlying cause, such as postoperative, traumatic, or infectious edema. Do not assign it if the laterality is not left eye or the record is nonspecific; check documentation.
Coding tip
Confirm both idiopathic cause and left-eye laterality in the provider note before assigning H18.222.