ICD-10 Code H18.712 – Corneal ectasia, left eye (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H18.712 – Corneal ectasia, left eye
What it is
H18.712 identifies corneal ectasia affecting the left eye. It means the cornea has thinned and bulged outward, creating an irregular shape that can distort vision.
Clinical signs
Common findings include progressive corneal thinning, steepening, and irregular astigmatism. Vision may be blurred or distorted; clinical features vary, so refer to documentation.
When to use this code
Use this code when the provider documents corneal ectasia limited to the left eye. It is appropriate for confirmed diagnoses in outpatient, specialty, or problem-list documentation. If the record does not specify the eye or the exact corneal disorder, check documentation before coding.
Do not use for
Do not use this code for bilateral corneal ectasia or ectasia documented in another eye. Avoid using it when the note describes a different corneal condition without clear ectasia.
Coding tip
Verify laterality carefully; H18.712 is specific to the left eye, so unspecified or bilateral documentation needs a different code.