ICD-10 Code H05.359 – Exostosis of unspecified orbit (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H05.359 – Exostosis of unspecified orbit
What it is
H05.359 identifies an exostosis, or bony growth, in the orbit when the side and exact orbital site are not documented. Use it for a benign-appearing osseous protrusion involving the eye socket.
Clinical signs
Clinical features vary; refer to documentation. Patients may have a palpable or imaging-detected bony mass, orbital fullness, or symptoms from local pressure on nearby structures.
When to use this code
Use this code when the provider documents exostosis of the orbit but does not specify right or left, or a more precise orbital location. It is also appropriate when imaging or exam confirms an orbital bony overgrowth and the record supports no further detail. Check documentation if the note uses a different orbital diagnosis.
Do not use for
Do not use this code for orbital tumors, cysts, inflammatory swelling, or non-bony orbital masses. If the documentation specifies a different orbital disorder or a more exact site, code that condition instead.
Coding tip
Verify laterality and the exact orbital site in the record before assigning H05.359.