Abstract: Objective To explore the value of magnetic resonance perfusion-weighted imaging(PWI) -diffusion-weighted imaging(DWI) mismatch to guide thrombolytic therapy beyond the time window(>6h) in patients with acute cerebral infarcts.Methods 40 patients with acute cerebral infarcts which were imaged by magnetic resonance and(PWI-DWI)/DWI×100%>30% within 12 hours after symptom onset were divided into thromobolytic group and control group. The patients in thromobolytic group were treated with intravenous rt-PA(0.6-0.9mg/kg), the controls were received common therapy. The two groups were scored with National Institutes of Health Stroke Scale(NIHSS)/Activities of Daily Living(ADL) score respectively at pre-thrombolysis, 1W, 2W and 3M after thrombolysis.Results The NIHSS score of the thromobolytic group at 1W, 2W and 3M after thrombolysis is lower than that of the control group(P<0.01), the ADL score of the thromobolytic group at 2W and 3M after thrombolysis is higher than that of the control group significantly(P<0.01).Conclusion Guided by PWI>DWI image, extending the time window for thrombolytic treatment of acute ischemic stroke is beneficial and feasible.

Key words: Diffusion magnetic resonance imaging; Tissue plasminogen activator; Thromobolytic therapy; Time

摘要： 目的 探讨磁共振灌注成像－弥散成像（perfusion weighted imaging-diffusion weighted imaging，PWI-DWI）不匹配对指导超时间窗（>6h）的急性缺血性卒中患者溶栓的价值。方法 选择在发病12h内完成磁共振检查，且（PWI-DWI）/DWI×100%>30%的40例急性缺血性卒中患者，分为溶栓组和对照组，溶栓组给予重组组织型纤溶酶原激活剂（recombinant tissue plasminogen activator，rt-PA）0.6～0.9mg/kg静脉溶栓治疗，对照组常规治疗。两组患者在溶栓前、溶栓后1周、2周、3个月分别行美国国立卫生院卒中量表（National Institutes of Health Stroke Scale，NIHSS）评分，溶栓前、溶栓后2周、3个月分别行日常生活能力量表（activities of daily living，ADL）评分。结果 溶栓组在溶栓后1周、2周、3个月NIHSS评分均较对照组降低（P<0.01）；在2周和3个月，溶栓组ADL评分较对照组明显升高（P<0.01）。结论 在PWI>DWI影像学模式指导下，适当延长急性缺血性卒中的溶栓时间窗具有可行性。

关键词: 磁共振成像; 弥散; 组织型纤溶酶原激活物; 时间