3.0T磁敏感加权成像在兔颅脑爆震伤早期出血灶检测及预后评估中的应用

Application of 3.0T Susceptibility Weighted Imaging in the Diagnosis of Hemorrhagic Foci and the Outcome Prediction of Rabbits with Brain Blast Injury

目的探讨磁敏感加权成像(SWI)对颅脑爆震伤早期出血灶检出率及预后评估作用,为临床治疗提供合理依据。方法对30只实验兔执行颅脑爆震,爆震后行常规CT/MRI及SWI扫描,采用后处理技术对感兴趣区进行量化分析,然后解剖实验兔颅脑进行病理组织学检查,与其SWI图像进行对照分析。结果 30只实验兔,经CT、T1WI、T2WI、SWI分别检出出血灶数目为22、102、221、738个,SWI序列检出出血灶数目多于常规T1WI、T2WI序列(χ2=10.00,P<0.01)。SWI序列显示出血灶形态呈点状(315,42.7%)、片状(218,29.5%)及线样(205,27.8%)低信号影,边缘清晰。存活实验兔经SWI序列检出出血灶数目与生存时间呈正相关(r=-0.667,P<0.05)。结论 SWI明显提高对出血灶的检出率,尤其是微小出血灶检出率,并且能够明确出血灶数目多少和分布部位,有预后评估作用,可为临床诊治提供指导依据。

Objective To investigate the value of susceptibility weighted imaging （SWI） in the diagno- sis of hemorrhagic foci early after blast injury and its role in the outcome prediction. Methods Totally 30 rabbits with blast-induced cerebral blast injury were used in this study. After routine CT/MRI and SWI scanning, quanti- fied analysis was performed in regions of interest using post-processing technology. After dissecting the brains of the experimental rabbits, the cerebral histopathological changes were observed, and the results were compared with SWI findings. Results In these 30 rabbits, 22, 102, 221, and 738 hemorrhagic foci were detected by CT, T1WI, T2WI, and SWI, respectively. The number of cerebral microbleeds detected by SWI was significantly lar- ger than those revealed by conventional T1WI and T2WI （~2 = 10. 00, P 〈0. 01 ） . Furthermore, the SWI ima- ging displayed the punctiform （n = 315, 42. 7% ）, lamellar （ n = 218, 29. 5% ）, slinar （ n = 205, 27. 8% ） hypointense foci, with clear margin. The number of hemorrhagic foci detected by SWI was positively correlated with survival （r = -0. 667, P 〈 0. 05） . Conclusions SWI remarkably increases the detection rate of hemorrhagic foci （particularly microbleeds） in rabbits with cerebral blast injury. The number of cerebral microbleeds and loca- tion of foci are closely related with the outcomes and therefore may facilitate clinical managment.