ICD-10 Code I63.539 – Cerebral infarction due to unspecified occlusion or stenosis of unspecified posterior cerebral artery (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I63.539 – Cerebral infarction due to unspecified occlusion or stenosis of unspecified posterior cerebral artery
What it is
This code identifies an ischemic stroke in the posterior cerebral artery territory when the artery is not further specified. It means brain tissue was injured because blood flow through that vessel was blocked or narrowed.
Clinical signs
Clinical features vary; refer to documentation. Posterior circulation infarcts may include visual field loss, sensory changes, memory problems, or other focal neurologic deficits consistent with cerebral ischemia.
When to use this code
Use this code when the provider documents cerebral infarction caused by occlusion or stenosis of an unspecified posterior cerebral artery and does not identify a more specific vessel or laterality. It fits confirmed ischemic stroke cases after imaging or clinical assessment supports infarction. Check documentation if the record only states stroke, TIA, or nonspecific cerebral ischemia.
Do not use for
Do not use it for hemorrhagic stroke, transient ischemic attack, or infarction from a clearly identified artery outside the posterior cerebral artery. If the documentation specifies a different vessel or mechanism, code that diagnosis instead.
Coding tip
Query the provider when the record names posterior circulation stroke but does not clearly document the artery or whether infarction was confirmed.