Is I66.1 a billable ICD-10-CM code?

No. I66.1 is a non-billable header code. Code to a higher level of specificity using one of its child codes.

Where does I66.1 sit in the tabular list?

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

I66.1

I66.1 — Occlusion and stenosis of anterior cerebral artery

Non-billable headerICD-10-CM

I66.1 is a non-billable header ICD-10-CM code for occlusion and stenosis of anterior cerebral artery. It cannot be billed on its own: choose one of the more specific child codes below.

Risk adjustment

I66.1 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 I66.1

4 child codes. Green means billable.

I66.11Occlusion and stenosis of right anterior cerebral artery
I66.12Occlusion and stenosis of left anterior cerebral artery
I66.13Occlusion and stenosis of bilateral anterior cerebral arteries
I66.19Occlusion and stenosis of unspecified anterior cerebral artery

Related codes at this level

Codes that share I66. If I66.1 is not quite right, the correct code is usually one of these.

I66.0Occlusion and stenosis of middle cerebral artery
I66.2Occlusion and stenosis of posterior cerebral artery
I66.3Occlusion and stenosis of cerebellar arteries
I66.8Occlusion and stenosis of other cerebral arteries
I66.9Occlusion and stenosis of unspecified cerebral artery

Questions about I66.1

Is I66.1 a billable ICD-10-CM code?: No. I66.1 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does I66.1 sit in the tabular list?: Diseases of the circulatory system (I00-I99), in the block Cerebrovascular diseases (I60-I69).