Dissection of cerebral arteries, nonruptured

This code describes a condition where the inner layers of a cerebral artery separate, creating a false lumen, without evidence of rupture or hemorrhage. This dissection can lead to narrowing or occlusion of the vessel, potentially causing ischemic stroke or transient ischemic attacks.

Use this code when documentation clearly indicates a non-hemorrhagic dissection of an intracranial artery. This diagnosis is often made via imaging studies such as CTA, MRA, or conventional angiography, showing an intimal flap, double lumen, or intramural hematoma without extravasation of contrast.

• Ensure documentation explicitly states "nonruptured" or absence of hemorrhage.
• Distinguish from ruptured cerebral artery dissections, which are coded differently.
• Code any associated neurological deficits (e.g., stroke, TIA) separately and sequence appropriately.