Occlusion and stenosis of unspecified precerebral artery

This code signifies a narrowing or blockage of a precerebral artery, such as the carotid or vertebral arteries, without specific identification of the affected vessel or the nature of the obstruction. It indicates an unconfirmed or generalized diagnosis of arterial insufficiency supplying the brain.

Use this code when documentation indicates an occlusion or stenosis of a precerebral artery but lacks specificity regarding the exact artery involved (e.g., "precerebral artery stenosis"). This code is appropriate when imaging or clinical findings confirm a blockage but do not differentiate between carotid, vertebral, or other precerebral vessels.

• Avoid using this code if the specific precerebral artery (e.g., carotid, vertebral) is documented; instead, use a more specific code from the I65 series.
• This code should be used as a last resort when more specific information is unavailable in the medical record.
• Query the provider for clarification if the documentation suggests a specific artery but does not explicitly name it.