目的 :用弥散加权 (diffusion weightedDW )MRI技术评价经动脉溶栓治疗急性脑梗塞的效果。材料和方法 :新西兰白兔 2 0只 ,随机分为 2组 ,每组 10只 ,颈内动脉注入血凝块栓子制成急性脑梗塞动物模型。实验组在栓塞后 4h经动脉给予尿激酶溶栓治疗。分别在栓塞后 1,3 ,6 ,12 ,2 4h行DW MRI系列扫描。测量并以 1h为基准计算缺血面积在各时间点的扩大程度 (百分比 )。结果 :栓塞后 1hDW MRI均可显示梗塞灶 ;与 1h点相比 ,非治疗组缺血面积在栓塞后 3 ,6 ,12 ,2 4h分别扩大了 2 3 1% ,2 5 6 % ,39 5 % ,43 4% ,而治疗组分别扩大了 19 5 % ,2 5 7% ,2 0 6 % ,19 7% ,两组间在 12h后差异显著 (P <0 0 1)。结论 :早期经动脉溶栓治疗在减轻急性脑梗塞损伤范围和程度上效果显著 ;DW MRI是诊断和监测急性脑梗塞治疗效果的很好影像学手段 Objective: To evaluate the effect of transarterial thrombolysis on acute cerebral infarction with diffusion weighted DW MRI. MATERIALS AND METHODS: Twenty New Zealand white rabbits were randomly divided into 2 groups (10 in each group). Animals were injected with blood clot embolus into the animal model of acute cerebral infarction. Experimental group 4h after embolization via urokinase thrombolytic therapy. The DW MRI scans were performed at 1, 3, 6, 12 and 24 hours after embolization. The extent of enlargement (percentage) of the ischemic area at each time point was measured and calculated on the basis of 1 hour. Results: Compared with 1h point, infarct size could be displayed by 1D DWI after embolization. Compared with 1h, ischemic area in non-treatment group increased by 21.3%, 25.6%, 395% at 3, 6, 12, 24 hours after embolization % And 43.4% respectively, while the treatment group expanded by 19.5%, 25.7%, 26.0% and 19.7% respectively. There was significant difference between the two groups after 12 hours (P <0.01). Conclusion: Early arterial thrombolysis is effective in reducing the extent and extent of acute cerebral infarction. DW MRI is a good imaging method to diagnose and monitor the therapeutic effect of acute cerebral infarction