ICDcodes.org
FY2027

I63.2 vs I65

I63.2 and I65 can never be reported together. ICD-10-CM declares them mutually exclusive with an Excludes1 note, meaning the two conditions cannot occur in the same patient — so exactly one of them is correct for any given encounter.

The official note, declared on I65
insufficiency of precerebral arteries causing cerebral infarction (I63.0-I63.2)
I63.2

Cerebral infarction due to unspecified occlusion or stenosis of precerebral arteries

Not billable
Chapter 9
Diseases of the circulatory system
Section
I60-I69
Indexed under
  • Infarct, infarction › cerebral › due to › occlusion NEC › precerebral arteries
  • Infarct, infarction › cerebral › due to › stenosis NEC › precerebral arteries
I65

Occlusion and stenosis of precerebral arteries, not resulting in cerebral infarction

Not billable
Chapter 9
Diseases of the circulatory system
Section
I60-I69
Use when the record says
  • embolism of precerebral artery
  • narrowing of precerebral artery
  • obstruction (complete) (partial) of precerebral artery
  • thrombosis of precerebral artery

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