ICD-10 I66.01
Billable / SpecificOcclusion and stenosis of right middle cerebral artery
About ICD-10-CM I66.01
ICD-10-CM code I66.01 represents Occlusion and stenosis of right middle cerebral artery. This is a billable/specific code in the Circulatory System chapter (block I66). The 2026 edition of ICD-10-CM I66.01 became effective on October 1, 2025.
Medicare LCD Coverage for I66.01
Local Coverage Determinations (LCDs) from CMS MACs that list I66.01 as a covered diagnosis.
Showing top 10 of 555 total . Click a CPT for full coverage scope.
Commercial Payer Coverage
Coverage policies from major commercial payers referencing I66.01.
4 Cigna
5 Medicare
CPT Codes Commonly Billed with I66.01
Procedures frequently paired with this diagnosis based on PayerReady's Dx↔Px linkage data.
We don't have CPT pairings indexed for this specific code yet. Use the CPT search above to find common procedures, or check your payer's published medical policy for code-specific guidance.
Convert I66.01 to ICD-9-CM
Per CMS General Equivalence Mappings (GEMs), useful for legacy data review and historical claim analysis.
| ICD-10 | ICD-9 | Mapping Flags |
|---|---|---|
| I66.01 | 43400 | 10000 |
| I66.01 | 43410 | 10000 |
| I66.01 | 43490 | 10000 |
Flags format (5 digits): Approximate · No Map · Combination · Scenario · Choice List. Source: CMS 2017 GEMs (final version).
Codes Adjacent To I66.01
Other codes in section I60-I69 (Cerebrovascular diseases).
ICD-10 I66.01, Billing FAQ
Is ICD-10 code I66.01 billable? +
Yes, I66.01 is a billable ICD-10-CM code that can appear as a primary or secondary diagnosis on claims.
What ICD-9 codes does I66.01 map to? +
Per CMS GEMs, I66.01 maps to ICD-9 codes: 43400, 43410, 43490. Useful for legacy data review and historical claim analysis.
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Reviewed by the PayerReady Medical Coding Team
Verified against the CMS 2026 code set on May 31, 2026.
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