ICD-10 Code I66.23 – Occlusion and stenosis of bilateral posterior cerebral arteries (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I66.23 – Occlusion and stenosis of bilateral posterior cerebral arteries
What it is
This code identifies narrowing or blockage in both posterior cerebral arteries, which supply blood to the occipital lobes and parts of the temporal and thalamic regions. Use it when the documentation specifically states bilateral posterior cerebral artery occlusion or stenosis.
Clinical signs
Clinical features vary; refer to documentation. Findings may include symptoms of posterior circulation ischemia, such as visual disturbance, sensory changes, or other focal neurologic deficits consistent with reduced blood flow in both vessels.
When to use this code
Use I66.23 when the provider documents bilateral posterior cerebral artery stenosis or occlusion, whether confirmed by imaging or stated in the assessment. It may appear in a stroke workup, vascular imaging report, or neurology note describing both arteries. If the side is not bilateral, choose the more specific laterality documented.
Do not use for
Do not use this code for nonspecific cerebral artery disease, embolic stroke without documented artery narrowing, or disease limited to one posterior cerebral artery. Check documentation if the vessel, laterality, or cause is unclear.
Coding tip
Look for the exact vessel name and bilateral laterality in the record before assigning this code.