Diffusion-Perfusion MRI in Superacute Cerebral Infarction: An Experimental Study in Rats

Objective To study superacute cerebral infarction with diffusion perfusion MRI in experimental rat model by occluding middle cerebral artery. Materials and Methods The total 34 rats were randomly divided into 5 groups. Group A (n=2) was control group and was used as sham operated rats. The remaining rats were divided into group B, C, D and E (n=8 each) with the middle cerebral artery occlusion time of 30 minutes, 1, 3 and 6 hours, respectively. At the end of the scheduled occlusion time, all rats of group B, C, D, and E were studied with diffusion weighted imaging (DWI) and perfusion imaging (PI). DWI and PI were repeated in rats of above groups at 2 and 24 hours after reperfusion of middle cerebral artery. DWI and PI were carried out in rats of group A at 2 and 24hours after the procedure.Results In sham operated rats of group A, no abnormal signal was seen on DWI and PI. In rats of group B, C, D and E, abnormal signal was seen on PI. The high intensity signal area on DWI enlarged with the time, and became the same size as the abnormal signal area on PI after 6 hours. High signal was seen on T 2WI in only 2 hours after the occlusion of middle cerebral artery.Conclusion The size, extent and development of superacute cerebral infarction can be well demonstrated on DWI, while the area of ischemia can be displayed on PI.