Intracranial Collaterals: The Next Frontier in Acute Ischemic Stroke?

Intracranial collateral pathways are important for providing perfusion to the ischemic brain regions affected by an intracranial occlusion [1]. These channels may be pre-existing and compensate for the reduced perfusion via the circle of Wilis or develop de-novo. The collateral status correlates well with final infarct volume and functional outcome [2]. These collaterals can also predict the effectiveness of intravenous thrombolysis as well as various endovascular interventions [3]. Furthermore, good collaterals reduce hemorrhagic complications of various therapeutic strategies in AIS [3].