ICD-10 Code I66.22 – Occlusion and stenosis of left posterior cerebral artery (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I66.22 – Occlusion and stenosis of left posterior cerebral artery
What it is
This code identifies narrowing or blockage of the left posterior cerebral artery, one of the brain’s blood vessels. It is used when documentation specifies the left side and the posterior cerebral artery.
Clinical signs
Clinical features vary; refer to documentation. Findings may include symptoms of posterior cerebral artery ischemia, such as visual field disturbance, altered visual perception, or other focal neurologic deficits.
When to use this code
Use I66.22 when the provider documents occlusion or stenosis affecting the left posterior cerebral artery. It may be supported by imaging, vascular studies, or a clear clinical diagnosis in the record. Code the condition only when the laterality and vessel are stated.
Do not use for
Do not use this code for nonspecific cerebrovascular disease, stroke without vessel detail, or stenosis of a different intracranial artery. Check documentation if the record does not clearly identify the left posterior cerebral artery.
Coding tip
Confirm both the side and the exact artery in the note before assigning I66.22.