ICD-10 Code H50.42 – Monofixation syndrome (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H50.42 – Monofixation syndrome
What it is
H50.42 identifies monofixation syndrome, a binocular vision disorder in which one eye has reduced foveal fixation while peripheral fusion remains intact. It is usually associated with a small-angle strabismus or amblyopia history.
Clinical signs
Typical findings include a small manifest deviation, reduced stereopsis, and suppression of the deviating eye on sensory testing. Clinical features vary; refer to documentation.
When to use this code
Use H50.42 when the provider documents monofixation syndrome as the diagnosis, even if the note also mentions a small strabismus or amblyopia history. It fits ophthalmology or optometry assessments describing stable binocular adaptation with reduced central fusion.
Do not use for
Do not use this code for unspecified strabismus, isolated amblyopia, or diplopia without documentation of monofixation syndrome. Check documentation if the record only notes ocular misalignment.
Coding tip
Code H50.42 only when the provider names monofixation syndrome; do not infer it from exam findings alone.