Table 1:

The original Thrombolysis in Cerebral Infarction perfusion scale²

Category	Title	Description
Grade 0	No Perfusion	No antegrade flow beyond the point of occlusion.
Grade 1	Penetration with Minimal Perfusion	The contrast material passes beyond the area of obstruction but fails to opacify the entire cerebral bed distal to the obstruction.
Grade 2	Partial Perfusion	The contrast material passes beyond the obstruction and opacifies the arterial bed distal to the obstruction. However, the rate of entry of contrast into the vessel distal to the obstruction and/or its rate of clearance from the distal bed are perceptibly slower than its entry into and/or clearance from comparable areas not perfused by the previously occluded vessel.
Grade 2a		Only partial filling (less than two-thirds) of the entire vascular territory is visualized.
Grade 2b		Complete filling of all of the expected vascular territory is visualized but the filling is slower than normal.
Grade 3	Complete Perfusion	Antegrade flow into the bed distal to the obstruction occurs as promptly as into the obstruction and clearance of contrast material from the involved bed is as rapid as from an uninvolved other bed of the same vessel or the opposite cerebral artery.