I66.9

ICD-10Billable

Occlusion and stenosis of unspecified cerebral artery

Official ICD-10-CM descriptor (FY2026)

Occlusion and stenosis of unspecified cerebral artery

I66.9 is valid for submission on a claim — CMS flags it as a billable, specific code.

Related codes in I66

I66.0Occlusion and stenosis of middle cerebral arterycategory
I66.1Occlusion and stenosis of anterior cerebral arterycategory
I66.2Occlusion and stenosis of posterior cerebral arterycategory
I66.3Occlusion and stenosis of cerebellar arteries
I66.8Occlusion and stenosis of other cerebral arteries

Where this code sits

Chapter: 9. Diseases of the circulatory system (I00-I99)
Block: Cerebrovascular diseases (I60-I69)
Parent code: I66

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Source

ICD-10-CM FY2026. Centers for Medicare & Medicaid Services (CMS) / National Center for Health Statistics (NCHS), “2026 ICD-10-CM Code Descriptions in Tabular Order” (icd10cm_order_2026.txt). Download the original file from cms.gov. Public domain (US Government work). Descriptors, billable flags and instructional notes on this page are reproduced from that file without modification. Krasyn adds no clinical guidance.