I66.9
BillableOcclusion and stenosis of unspecified cerebral artery
Occlusion and stenosis of unspecified cerebral artery
Coding Notes
Includes
Conditions included under this code
- embolism of cerebral artery
- narrowing of cerebral artery
- obstruction (complete) (partial) of cerebral artery
- thrombosis of cerebral artery
Excludes 1
Codes that cannot be used together with this code (mutual exclusion)
Excludes 2
Conditions not included here, but the patient may have both
- •certain conditions originating in the perinatal periodP04-P96
- •certain infectious and parasitic diseasesA00-B99
- •complications of pregnancy, childbirth and the puerperiumO9A)O00
- •congenital malformations, deformations, and chromosomal abnormalitiesQ00-Q99
- •endocrine, nutritional and metabolic diseasesE00-E88
- •injury, poisoning and certain other consequences of external causesS00-T88
- •neoplasmsC00-D49
- •symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classifiedR00-R94
- •systemic connective tissue disordersM30-M36
- •transient cerebral ischemic attacks and related syndromesG45
Use Additional Code
Additional codes that should follow this code
Related Codes(5)
ICD-11 Equivalents(1)
ICD-11 Equivalents
View full mappingCorresponding ICD-11 codes from the WHO crosswalk mapping
Also Known As / Clinical Terms(58)
SNOMED CT
- Cerebral arterial occlusion20059004
- Cerebral artery occlusion20059004
- Occlusion of cerebral artery20059004
- Cerebral arterial thrombosis71444005
- Cerebral thrombosis71444005
- Thrombosis of cerebral artery71444005
- Thrombus of cerebral artery71444005
- Cerebral arterial embolism75543006
- Cerebral embolism75543006
- Progressive intracranial arterial occlusion89142007
- Occlusion and stenosis of multiple and bilateral cerebral arteries195236009
- Intracranial septic embolism230220006
- Intracranial arterial septic embolism230221005
- Cholesterol embolisation syndrome236489002
- Cholesterol embolization syndrome236489002
- Cholesterol embolus syndrome236489002
- Impending cerebrovascular accident286742002
- Septic arterial embolism442105001
- Septic embolus of artery442105001
- Transient ischaemic attack due to embolism710575003
- Transient ischemic attack due to embolism710575003
- Asymptomatic stenosis of intracranial artery724427002
- Stenosis of cerebral artery838275008
- Cholesterol atheroembolism of cerebrum1204128009
- Cholesterol atheroembolism to cerebrum1204128009
- Cholesterol atheromatous embolism of cerebrum1204128009
- Infective occlusion of cerebral artery1204202004
- Occlusion of cerebral artery due to infection1204202004
UMLS
Clinical Terms
- Transient ischemic attack due to embolism
- Intracranial septic embolism
- Thrombosis of cerebral artery
- Intracranial arterial septic embolism
- Impending cerebrovascular accident
- Cholesterol embolus syndrome
- Cholesterol atheromatous embolism of cerebrum
- Cerebral arterial occlusion
- Septic embolus of artery
- Cerebral thrombosis
- Infective occlusion of cerebral artery
- Cholesterol embolisation syndrome
- Occlusion of cerebral artery
- Cerebral artery occlusion
- Occlusion and stenosis of multiple and bilateral cerebral arteries
- Thrombus of cerebral artery
- Cerebral arterial embolism
- Cholesterol atheroembolism of cerebrum
- Asymptomatic stenosis of intracranial artery
- Septic arterial embolism
- Cholesterol atheroembolism to cerebrum
- Stenosis of cerebral artery
- Occlusion of cerebral artery due to infection
- Progressive intracranial arterial occlusion
- Cerebral embolism
- Cholesterol embolization syndrome
- Cerebral arterial thrombosis
- Transient ischaemic attack due to embolism
Frequently Asked Questions
What is the ICD-10 code for occlusion and stenosis of unspecified cerebral artery?
The ICD-10-CM code for occlusion and stenosis of unspecified cerebral artery is I66.9. The full clinical description is "Occlusion and stenosis of unspecified cerebral artery". I66.9 is a billable/specific code that can be used on insurance claims and medical billing.
What does ICD-10 code I66.9 mean?
ICD-10-CM code I66.9 represents “Occlusion and stenosis of unspecified cerebral artery”. It is classified under Chapter 9: Diseases of the Circulatory System and is a billable/specific code that can be used on a claim.
Is I66.9 a billable code?
Yes, I66.9 is a billable/specific ICD-10-CM code and can be used to indicate a diagnosis on a medical claim.
What chapter is I66.9 in?
I66.9 is in Chapter 9: Diseases of the Circulatory System (codes I00-I99).
What codes cannot be used with I66.9?
I66.9 has Excludes1 notes indicating codes that cannot be used together with it, including: traumatic intracranial hemorrhage (S06.-); Occlusion and stenosis of cerebral artery causing cerebral infarction (I63.3-I63.5).
Are additional codes required with I66.9?
Yes, when using I66.9, also report: presence of:; alcohol abuse and dependence (F10.-); exposure to environmental tobacco smoke (Z77.22); history of tobacco dependence (Z87.891); hypertension (I10-I1A); occupational exposure to environmental tobacco smoke (Z57.31); tobacco dependence (F17.-); tobacco use (Z72.0).
What SNOMED CT codes does I66.9 map to?
I66.9 maps to 15 SNOMED CT concepts: 724427002, 75543006, 20059004, 71444005, 1204128009, and 10 more. SNOMED CT is a clinical terminology used in electronic health records.
What are the UMLS CUIs for I66.9?
I66.9 is linked to 1 UMLS Concept Unique Identifier: C0494612. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.
How does I66.9 relate to ICF functioning codes?
ICF (International Classification of Functioning, Disability and Health) codes describe how conditions like occlusion and stenosis of unspecified cerebral artery affect a person's functioning — body functions, activities, participation, and environmental factors. AutoICD provides ICF Core Sets for 12+ conditions and can map clinical text to ICF categories automatically. Browse the ICF directory to explore functioning codes.
What is the ICD-11 equivalent of I66.9?
I66.9 maps to the ICD-11 code: 8B2Z (Cerebrovascular diseases, unspecified).
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Includes SNOMED Clinical Terms® (SNOMED CT®) used by permission of SNOMED International. Includes content from the UMLS Metathesaurus, courtesy of the U.S. National Library of Medicine.