ICD-10 Code I63.039 – Cerebral infarction due to thrombosis of unspecified carotid artery (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I63.039 – Cerebral infarction due to thrombosis of unspecified carotid artery
What it is
This code identifies an ischemic stroke caused by a blood clot in a carotid artery, but the record does not specify whether the right or left side is involved. Use it when the documentation clearly states carotid thrombosis as the cause.
Clinical signs
Typical findings include sudden focal neurologic deficits such as unilateral weakness, speech difficulty, facial droop, or vision loss. Clinical features vary; refer to documentation and imaging support when available.
When to use this code
Use I63.039 when the provider documents cerebral infarction due to thrombosis of an unspecified carotid artery and does not identify laterality. It fits acute stroke admissions, emergency evaluations, or follow-up notes that confirm the infarct cause. Check documentation if the chart only says carotid disease or stroke without a clear thrombotic cause.
Do not use for
Do not use this code for embolic stroke, hemorrhagic stroke, or carotid stenosis without infarction. If the record specifies right or left carotid artery, choose the laterality-specific code instead.
Coding tip
Verify both the infarct type and the artery side in the provider note before assigning this unspecified laterality code.