Excludes1 pair
I67.7 vs I77.6
I67.7 and I77.6 are not coded together. ICD-10-CM declares them mutually exclusive with an Excludes1 note — the two conditions are not expected to occur together, so exactly one of them is normally correct for a given encounter. The Official Guidelines carve out one exception: if the two conditions are clearly unrelated to each other, both may be reported.
The official note, declared on I77.6
cerebral NEC (I67.7)
I67.7
Cerebral arteritis, not elsewhere classified
BillableUnspecified
- Chapter 9
- Diseases of the circulatory system
- Section
- I60-I69
Use when the record says
- Granulomatous angiitis of the nervous system
Indexed under
- Angiitis › nervous system, granulomatous
- Arteritis › brain
- Arteritis › cerebral
- Endarteritis › brain
- Endarteritis › cerebral or cerebrospinal
I77.6
Arteritis, unspecified
BillableUnspecified
- Chapter 9
- Diseases of the circulatory system
- Section
- I70-I79
Use when the record says
- Aortitis NOS
- Endarteritis NOS
Indexed under
- Angiitis
- Aortitis (nonsyphilitic) (calcific)
- Arteriolitis
- Arteritis
- Endarteritis (bacterial, subacute) (infective)
Excludes1 is not always absolute: where two conditions covered by the note are genuinely unrelated, CMS guidance permits reporting both. Document the reasoning rather than assuming it. More on Excludes1 vs Excludes2 · FY2027