ICD-10 Code I63.521 – Cerebral infarction due to unspecified occlusion or stenosis of right anterior cerebral artery (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I63.521 – Cerebral infarction due to unspecified occlusion or stenosis of right anterior cerebral artery
What it is
This code identifies an ischemic stroke affecting the right anterior cerebral artery territory when the blockage or narrowing is not further specified. It tells you the infarction is in the brain and linked to the right ACA.
Clinical signs
Clinical features vary; refer to documentation. Common ACA-territory findings may include weakness or sensory loss greater in the leg than the arm, gait difficulty, and behavioral or language changes depending on lesion location.
When to use this code
Use this code when the provider documents a cerebral infarction caused by unspecified occlusion or stenosis of the right anterior cerebral artery. It is appropriate when imaging or notes confirm the artery and side, but the occlusion type is not detailed. Check documentation if the record instead describes hemorrhage, transient ischemia, or a different vascular territory.
Do not use for
Do not use this code for cerebral infarction of the left ACA, bilateral ACA disease, or infarction from a clearly documented embolic or thrombotic mechanism coded elsewhere. Check documentation when the diagnosis is not a completed infarct.
Coding tip
Verify both laterality and vessel before assigning I63.521, because the right ACA designation is essential to correct code selection.