Zonal distribution of prominent vessel sign on the first magnetic resonance imaging scan and presence of infarct growth on the second scan.

* Infarcts in M1 to M6 (6 zones of the territory of the middle cerebral artery) were estimated using the Alberta Stroke Program Early CT Score (ASPECTS) system. PVS(+)/PVS(–), positive/negative prominent vessel sign on first MRI; IG(+)/IG(–), with/without infarct growth on second MRI. Zonal distribution of prominent vessel sign on the first magnetic resonance imaging scan and presence of infarct growth on the second scan.