ICD-10 Code I65.9 – Occlusion and stenosis of unspecified precerebral artery (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I65.9 – Occlusion and stenosis of unspecified precerebral artery
What it is
This code identifies narrowing or blockage of a precerebral artery, but the specific vessel is not documented. Use it when the record confirms disease of a precerebral artery without naming the exact artery.
Clinical signs
Clinical features vary; refer to documentation. Patients may have neurologic symptoms consistent with reduced blood flow, but the diagnosis should be supported by imaging or provider assessment of arterial occlusion or stenosis.
When to use this code
Use I65.9 when the clinician documents occlusion or stenosis of a precerebral artery and does not specify the carotid or another named vessel. It also fits when laterality or exact artery is unavailable in the note. If the documentation names a specific artery, code that more precise diagnosis instead.
Do not use for
Do not use this code for cerebral artery disease or for transient ischemic attack without documented precerebral artery narrowing or blockage. Check documentation if the vessel is specified elsewhere.
Coding tip
Query for the exact artery and laterality whenever possible, because a more specific code may be available.