The Effect Of Fluid-attenuated Inversion Recovery Imaging Hyperintensity On Intravenous Thrombolysis Of Acute Stroke Of Anterior Circulation

Objective:Including two parts, this study aims to explore the effect of fluid-attenuated inversion recovery imaging (FLAIR) lesional parenchymal hyperintensity (FPH) and vascular hyperintensity (FVH) on intravenous thrombolysis of acute ischemic stroke of anterior circulation.Methods:We retrospectively reviewed the clinical and imaging data of intravenous thrombolytic patients with acute anterior circulation infarction admitted during May2009to December2013. The presence of FPH and FVH were evaluated, and their associations with reperfusion, hemorrhagic transformation and clinical outcome after thrombolysis were assessed. Results:Ninety-five patients were analyzed. FPH were detectable in39(47.1%)cases. A longer time window of onset to imaging(OIT)was independently associated with FPH (OR=1.011,95%CI:1.004-1.018; P=0.003), which independently predicted a lower probability of reperfusion (OR=0.203,95%CI:0.043-0.961; P=0.044) and poor neurological outcome at3months(OR=5.461,95%CI:1.346-22.151; P=0.017). Besides, we found no association between FPH and baseline NIHSS or initial infarct or perfusion lesions, nor between FPH and hemorrhagic transformation(43.5%vs.34.6%; P=0.434). FVH were detectable in57(60.0%) cases. Patients with FVH had higher NIHSS (7.2±4.5vs.12.1±6.1; P<0.001), larger initial DWI lesions (2vs.5.5; P=0.002), perfusion lesions (3vs.73.5; P<0.001), and a higher rate of hemorrhagic transformation (80.8%vs.52.2%; P=0.011),compared with those without FVH. Proximal large vessel occlusion(OR=48.712,95%CI:7.772-305.326; P<0.001)were independently associated with the presence of FVH. The later one is associated with a larger PWI-DWI mismatch (OR=8.557,95%CI:2.592±28.245; P<0.001), but may not statistically predicted a higher rate of reperfusion (OR=0.441,95%CI:0.089-2.179; P=0.315) or hemorrhagic transformation(OR=1.079,95%CI:0.278-4.181; P=0.913), whereas, independently predicted the poor neurological outcome at3months(OR=3.826,95%CI:1.125-13.257; P=0.032). However, early reperfusion was associated with favorable outcome in patients with FVH after intravenous thrombolysis(OR=14.908,95%CI:2.100-105.852; P=0.007).Conclusion:The presence of FPH is associated with a longer duration time of ischemic event and a lower reperfusion rate. While FVH is associated with proximal large vessel occlusion, more severe stroke and a larger PWI-DWI mismatch. Neither will increase the hemorrhagic transformation risk, but both independently predict poor outcome at3months in patients with intravenous thrombolysis. Early reperfusion among patients with FVH can improve the outcome. Thus, we conclude that FPH may serve as a good tissue clock, and that FVH may require for an intensive reperfusion therapy.