运用磁共振Bold-fMRI、DWI及DTI成像技术探索兔严重烧伤早期脑组织损伤的神经机制  

Study on Mechanism of rabbits brain injury in early stage of severe burn based on magnetic resonance imaging Bold-f MRI,DWI and DTI imaging technology

作　　者：姜胜攀 谭一清 郑石林 雷文峰 王富华 洪帆 刘玄 JIANG Sheng-pan;TAN Yi-qing;ZHENG Shi-lin(Department of Interventional Radiology,Wuhan Third Hospital,Tongren Hospital of Wuhan University,Wuhan Hubei 430074,China)

机构地区：[1]武汉市第三医院(武汉大学附属同仁医院)介入医学科,湖北武汉430074

出　　处：《临床和实验医学杂志》2018年第19期2061-2064,共4页Journal of Clinical and Experimental Medicine

基　　金：武汉市卫生与计划生育委员会项目基金资助(编号:WX16D13)

摘　　要：目的运用磁共振血氧水平依赖功能磁共振成像技术(Bold-f MRI)、弥散加权成像(DWI)及弥散张量成像(DTI)成像技术,探讨严重烧伤早期脑组织损伤的神经机制。方法研究采用前瞻性实验设计,35只健康雄性新西兰大白兔随机分成对照组及烧伤组(烧伤后1 h、2 h、3 h、4 h、5 h、6 h)。采用体表烫伤法制作兔严重烧伤模型。运用磁共振Bold-f MRI、DWI及DTI成像技术采集相关磁共振图像,最后计算各组的表观弥散系数(ADC值)、各向异性分数值(FA值)、烧伤前后全脑肯德尔系数(Re Ho值)以及脑含水量的变化情况。分析烧伤后脑含水量与ADC值、FA值、Re Ho值的相关性。结果与对照组相比,烧伤后4~6 h兔脑所测感兴趣区(ROI)范围内ADC值出现显著降低,两者间差异有统计学意义(P<0.05);而烧伤后各时间节点的FA值未见明显变化,差异无统计学意义(P>0.05)。和正常对照组相比,烧伤后兔脑主要表现为双侧额叶、岛叶及左侧丘脑间的Re Ho值显著上升;而在右侧楔前叶、海马旁回及双侧颞叶Re Ho值显著下降。与正常对照组相比,烧伤后兔脑含水量明显增加,且在1~6 h内呈缓慢升高的趋势,尤以烧伤后3 h为著。进一步与影像学资料进行相关性分析后发现:烧伤后脑含水量与ADC值呈负相关(r=-0.867,P<0.01),与FA值无明确相关性(r=0.147,P=0.524),而与Re Ho值呈正相关(r=0.734,P<0.01)。结论重度烧伤后出现神经功能损害的神经机制可能是由于细胞毒性脑水肿引起,为烧伤患者治疗方案的选择奠定了可靠地理论基础。Objective Magnetic resonance imaging （Bold-fMRI）, DWI and DTI imaging techniques were used to explore the neural mechanism of brain injury in early stage of severe burn. Methods 35 healthy male New Zealand white rabbits were randomly divided into a control group and a burn group （1 h, 2 h, 3 h, 4 h, 5 h, 6 h after burn）. The model of severe burn in rabbits was made by the method of body surface scald. The MRI images were collected by magnetic resonance Bold-fMRI, DWI and DTI imaging techniques. The apparent diffusion coefficient （ADC）, the anisotropy value （FA）, the whole brain Kendall＇s coefficient （ReHo value） before and after burn and the change of brain water content were calculated. Results Compared with the control group, the ADC values in the ROI range of 4～6 h rabbits after burn were significantly reduced, and there was a significant difference between the two groups （ P 〈0.05）, but the FA value of the nodes in each time after burn did not change significantly （ P 〉0.05）. Compared with the normal control group, the ReHo value of the rabbit brain was significantly increased in the bilateral frontal lobe, the insula and the left thalamus, while the ReHo value of the right anterior lobe, the parahippocampal gyrus and the bilateral temporal lobe decreased significantly. Compared with the normal control group, the water content of the rabbit brain increased significantly after burn, and increased slowly at 1~6 h, especially after 3 h of burn. Further correlation analysis with imaging data showed that the water content of the brain was negatively correlated with the ADC value after burn （ r =-0.867, P 〈0.01）, and there was no definite correlation with FA （ r =0.147, P =0.524）, and positive correlation with ReHo value （ r =0.734, P 〈0.01）. Conclusion The neural mechanism of neurologic impairment after severe burn may be caused by cytotoxic brain edema, which provides important data basement for the treatment of burn.

关 键 词：兔 烧伤 磁共振成像 血氧水平依赖功能磁共振成像技术 扩散加权成像 弥散张量成像 神经机制 

分 类 号：R445.2[医药卫生—影像医学与核医学] R644[医药卫生—诊断学]