I66.9

I66.9: Occlusion and stenosis of unspecified cerebral artery

Billable / specific codeICD-10-CM

I66.9 is a billable, specific ICD-10-CM code for occlusion and stenosis of unspecified cerebral artery. It is valid for submission on a claim.

Check I66.9 with the rest of the claim: free scrubber

Excludes1 inherited from the categories above I66.9

A category’s note binds every code beneath it.

Written on I66: Occlusion and stenosis of cerebral arteries, not resulting in cerebral infarction

Occlusion and stenosis of cerebral artery causing cerebral infarction (I63.3-I63.5)

Risk adjustment

No CMS-HCC V28 category: this code does not change a RAF score.

Medicare coverage

I66.9 is named in 12 Medicare coverage policies: 12 listing it as supporting medical necessity. Which one applies depends on your Medicare contractor.

A52868Billing and Coding: Transesophageal Echocardiography (TEE)
A56551Billing and Coding: Visual Fields Testing
A56631Billing and Coding: Thoracic Aortography and Carotid, Vertebral, and Subclavian Angiography
A56722Billing and Coding: Intraoperative Neurophysiological Testing

Alphabetic index entries that lead here

Thrombosis, thrombotic›cortical
Thrombosis, thrombotic›intracranial(arterial)
Occlusion, occluded›artery›brain or cerebral
Occlusion, occluded›artery›cerebral

Code history

Unchanged in every release from FY2024 to FY2027.