Anterior circulation: There is cut off of the proximal left M1 segment, mild flow related signal is seen within left MCA branches and sylvian fissure, suggesting reconstitution via collaterals. Visualized right internal carotid artery, right M1 and A1 segments are widely patent. There is a patent anterior communicating artery. Small right posterior communicating artery is seen. Left posterior communicating artery is hypoplastic or absent.
Posterior circulation: No flow-limiting stenosis or dissection.