Occlusion and stenosis of other precerebral arteries

This code signifies a narrowing or blockage in any precerebral artery other than the carotid or vertebral arteries. These arteries supply blood to the brain before branching into the cerebral circulation. This condition can lead to reduced blood flow to the brain, potentially causing transient ischemic attacks (TIAs) or strokes.

Use this code when documentation specifies occlusion or stenosis of precerebral arteries not otherwise classified, such as the subclavian artery or innominate artery, when these conditions are causing cerebral ischemia. This code is appropriate when the specific affected precerebral artery is identified, but it is not a carotid or vertebral artery.

• Ensure documentation clearly specifies a precerebral artery other than carotid or vertebral.
• Do not use this code if the occlusion/stenosis is definitively identified as carotid (I65.2-) or vertebral (I65.0-).
• Consider an additional code for any associated cerebral infarction (I63.-) or transient cerebral ischemic attack (G45.-) if documented.