3.0T MR R2'在急性脑梗死中的初步应用

Objective To explore the characteristics of R2' in acute cerebral infarction, comparing with DWI and estimating the value on judging the infarction core and ischemic penumbra (IP). Methods Totally of 14 patients with acute cerebral infarction within 24 h of symptom onset were analyzed. Mean time from symptom onset to hospital was (16.73±4.65)h (6-22 h). Patients underwent MR on treatment the same day and 7-20 days after treatment. The lesions on DWI on treatment the same day was defined initial lesion (L0), whereas the final infarct size was defined on T2WI or T2-FLAIR in 7-20 days after treatment. Lesion growth (LG) was derived by subtracting L0 from F7-20, and surviving tissue (ST) was calculated by subtracting F7-20 from L0. The lesion shape was manually drawn in each picture and then compared each other. Results Three conditions were observed about the area of abnormal signal intensity on R2' and DWI in the initial inspection: ①Area of lessions of 4 patients in R2'map were bigger than in DWI. The initial lesion showed slightly high signal intensity on R2', whereas LG was higher than that in L0 and surrounding tissue. ② R2'=DWI, 6 cases. The area of lesions on DWI and R2'were equal on both initial inspection and F7-20. ③R2'<DWI，4 cases. Center of lesions were low signal intensity on R2'surrounded by high signal intensity. The final infarct size were similar to that of low signal intensity on initial inspection. Conclusion ①Within 24 hours since symptom onset, cerebral infarct lesion can be divided into three conditions. They respectively have different developing processes. ②R2' imaging has more accuracy in showing infarct core and ischemic penumbra than conventional MR.