Clinical Value Of Susceptibility Vessel Sign In Intravenous Thrombolysis And Endovascular Treaement Of Acute Ischemic Stroke Patients

Background: Acute ischemic stroke(AIS),a clinical syndrome,caused by sudden interruption of local blood supply and followed by brain tissue hypoxia and necrosis,is manifested by a series of neurological defective symptoms,the most promising medical intervention of which is by restoring regional blood flow promptly.It is difficult to choose the most suitable therapeutic method for each individual patient of AIS in early stage,on account of the benefits and risks.The thrombi in occlusive vessels may be seen as hypointense signals in magnetic resonance imaging(MRI)scans,which is due to the magnetic susceptibility effect of paramagnetic components of the thrombi and referred to as susceptibility vessel sign(SVS).Objective:We aim to figure out the prognostic value of SVS in stroke subtype,recanalization rate and outcomes in patients receiving intravenous thrombolysis(IVT)or endovascular therapy(EVT).Methods: Clinical researches published in the Embase,Pub Med and Cochrane Library electronic databases up to 26 August,2017 were identified for analysis.Two reviewers extracted data and conducted quality assessment independently.Statistical tests were performed to check forheterogeneity and publication bias,and sensitivity analysis was also performed to evaluate the stability of the conclusions.Results: Twenty-one studies involving 1832 patients met the inclusion criteria.The presence of SVS was significantly associated with cardioembolic stroke than absence of SVS(RR=1.53,95% CI:1.30-1.81,P<0.001).Patients with SVS were prone to obtaining non-recanalization(RR=0.70,95%CI: 0.56-0.88,P=0.002)and poor functional outcome(RR=1.68,95%CI: 1.44-1.97,P<0.001)after IVT,however,not after EVT(P=0.990 and P=0.335).The SVS length was smaller in recanalization group than in non-recanalization group(RR=-0.49,95% CI:-0.72-0.27,P<0.001).Meanwhile,no significant difference in SVS width was found between recanalization group and non-recanalization group.Conclusions: The present study demonstrated that the presence of SVS was a stronger predictor of cardioembolic stroke.In addition,the SVS was significantly associated with lower recanalization rate and poorer outcome in AIS patients after IVT,whereas,there was no significant difference after EVT.Thus,we should be more cautious when proceeding IVT in patients with SVS,and it might be more appropriate to implement EVT or combination therapy in the early onset.