ICD-10 Code I63.81 – Other cerebral infarction due to occlusion or stenosis of small artery (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I63.81 – Other cerebral infarction due to occlusion or stenosis of small artery
What it is
This code identifies an ischemic stroke caused by blockage or narrowing of a small cerebral artery, but not one classified in a more specific infarction category. Use it when the record documents a small-vessel brain infarct and the exact subtype is not further specified.
Clinical signs
Patients may have sudden focal neurologic deficits such as weakness, numbness, speech difficulty, or coordination problems. Imaging or clinical documentation should support an acute cerebral infarction; clinical features vary, so refer to documentation.
When to use this code
Use I63.81 when the provider documents an ischemic stroke or cerebral infarction due to occlusion or stenosis of a small artery and no more specific code applies. It fits cases where the anatomy is described as small-vessel or small-artery involvement. If laterality or a different infarction subtype is documented, code that more specific diagnosis instead.
Do not use for
Do not use this code for hemorrhagic stroke, transient ischemic attack, or cerebral infarction from a clearly different vessel category. Check documentation if the record only says “stroke” without confirming infarction or small-artery involvement.
Coding tip
Confirm the provider’s wording for “small artery” or “small-vessel” infarction before assigning this code.