TABLE 1. Cerebrovascular injury grading scale based on angiographic appearance.

Grade	Description
I	Irregularity of vessel wall or a dissection/intramural hematoma with <25% luminal stenosis
II	Intraluminal thrombus or visualized raised intimal flap, or dissection/intramural hematoma with ≥25% luminal narrowing
III	Pseudoaneurysm
IV	Vessel occlusion
V	Vessel transaction or hemodynamically significant arteriovenous fistula