Cerebral arteritis, not elsewhere classified

This diagnosis code signifies inflammation of the cerebral arteries that is not attributable to a systemic vasculitis or other specified cause. It represents an inflammatory process affecting the blood vessels supplying the brain, which can lead to various neurological deficits.

Assign this code when documentation specifies cerebral arteritis without further classification or when it is explicitly stated as "not elsewhere classified." This is appropriate when the underlying cause of the cerebral artery inflammation is unknown or not a recognized systemic vasculitis.

• Ensure documentation clearly states "cerebral arteritis, not elsewhere classified" or similar phrasing indicating an unspecified etiology.
• Review the Excludes1 note carefully; do not code this alongside allergic granulomatous angiitis (M30.1).
• Investigate if a more specific type of vasculitis affecting the cerebral arteries is documented, as those would be coded elsewhere.