ICD-10 Code H52.51 – Internal ophthalmoplegia (complete) (total) (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H52.51 – Internal ophthalmoplegia (complete) (total)
What it is
H52.51 identifies complete internal ophthalmoplegia, meaning the eye’s internal focusing and pupil-control muscles are not functioning normally. Use it when documentation specifically states total involvement.
Clinical signs
Findings may include a fixed or poorly reactive pupil and loss of accommodation. Clinical features vary; refer to documentation for the exact extent of ocular motor involvement.
When to use this code
Use this code when the provider documents internal ophthalmoplegia as complete or total. It may appear in ophthalmology or neurology notes describing impaired pupil response and accommodation.
If the record only mentions partial involvement, another code may be more appropriate. Check documentation when the diagnosis is uncertain or when the term is used without severity.
Do not use for
Do not use it for external ophthalmoplegia, generalized eye movement disorders, or nonspecific visual complaints. Check documentation if the note does not clearly state complete internal ophthalmoplegia.
Coding tip
Code the exact wording in the chart, and confirm whether “complete,” “total,” or another qualifier is documented before assigning H52.51.