Is I65 a billable ICD-10-CM code?

No. I65 is a non-billable header code. Code to a higher level of specificity using one of its child codes.

Where does I65 sit in the tabular list?

Diseases of the circulatory system (I00-I99), in the block Cerebrovascular diseases (I60-I69).

What cannot be coded together with I65?

I65 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.

I65

I65 — Occlusion and stenosis of precerebral arteries, not resulting in cerebral infarction

Non-billable headerICD-10-CM

I65 is a non-billable header ICD-10-CM code for occlusion and stenosis of precerebral arteries, not resulting in cerebral infarction. It cannot be billed on its own: choose one of the more specific child codes below.

Excludes1 — never code together

These conditions cannot occur together. Billing both on the same encounter is a denial.

insufficiency, NOS, of precerebral artery (G45.-)
insufficiency of precerebral arteries causing cerebral infarction (I63.0-I63.2)

Includes

Conditions this code covers.

embolism of precerebral artery
narrowing of precerebral artery
obstruction (complete) (partial) of precerebral artery
thrombosis of precerebral artery

Risk adjustment

I65 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Code to one of these instead I65

5 child codes. Green means billable.

Questions about I65

Is I65 a billable ICD-10-CM code?: No. I65 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does I65 sit in the tabular list?: Diseases of the circulatory system (I00-I99), in the block Cerebrovascular diseases (I60-I69).
What cannot be coded together with I65?: I65 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.