›› 2012, Vol. 32 ›› Issue (11): 1476-.doi: 10.3969/j.issn.1674-8115.2012.11.017

• 论著(基础研究) • 上一篇    下一篇

3.0T弥散加权成像和弥散张量成像对颅脑爆震伤诊断和预后评估的实验研究

吴 朋1, 吕国士2, 韩 峰2, 许克宁2, 王海辰2   

  1. 1.河北北方学院 研究生院, 2.中国人民解放军第251医院影像中心, 张家口 075000
  • 出版日期:2012-11-28 发布日期:2012-11-30
  • 通讯作者: 吕国士, 电子信箱: lament-378@163.com。
  • 作者简介:吴 朋(1985—), 男, 硕士生;电子信箱: 1353152923@qq.com。

Experimental study of 3.0T diffusion weighted imaging and diffusion tensor imaging in diagnosis and outcome prediction of cerebral blast injury

WU Peng1, LÜ|Guo-shi2, HAN Feng2, XU Ke-ning2, WANG Hai-chen2   

  1. 1.School of Graduate Studies, Hebei North University, Zhangjiakou 075000, China;2.Department of Radiology, 251 Hospital of PLA, Zhangjiakou 075000, China
  • Online:2012-11-28 Published:2012-11-30

摘要:

目的 探讨弥散加权成像(DWI)和弥散张量成像(DTI)序列对兔颅脑爆震伤早期非出血灶、白质纤维束损伤的诊断价值及预后评估作用,旨在为临床治疗提供合理依据。方法 以30只新西兰大白兔作为实验对象,建立颅脑爆震伤模型,伤后常规进行CT、磁共振成像(MRI)、DWI和DTI扫描,采用Functool 2后处理技术对感兴趣区域进行量化分析;观察颅脑组织病理学改变,并与其同一层面DWI和DTI图像进行对照分析。结果 30只实验兔中,6只CT、T1WI和T2WI序列显示脑内无异常信号影,其中2只DWI未发现任何异常低信号;在其余24只实验兔,CT仅见脑内积气影;MRI常规序列检出非出血灶,表现为T1WI稍低信号或低信号,T2WI 呈高信号;DWI序列显示亮白高信号影。DWI序列共检出非出血灶189个,分别呈现点状(28.5%)、片状(54.0%)和线样(17.5%)高信号影,边缘清晰。DWI序列检出非出血灶数目显著多于常规T1WI和T2WI序列(P<0.01)。DTI显示感兴趣区域的表观弥散系数(ADC)值和各向异性分数(FA)值降低,内囊区降低尤为显著(P<0.01)。大脑半球白质和脑干ADC值、FA值降低程度与实验兔的生存时间呈线性相关(r=0.53,P=0.05;r=0.13,P=0.03;r=0.25,P=0.04;r=0.27,P=0.02)。结论 对于兔颅脑爆震伤,DWI对非出血灶,尤其对小片状非出血灶的检出率较高;DTI可通过测定ADC值和FA值的降低程度在预后评估中发挥作用。

关键词: 爆震伤, 弥散加权成像, 弥散张量成像, 磁共振成像

Abstract:

Objective To investigate the value of diffusion weighted imaging (DWI) and diffusion tensor imaging (DTI) in diagnosis of non-hemorrhagic foci and white matter fiber injury early after blast in rabbits, and explore their role in outcome prediction. Methods Thirty New Zealand rabbits were selected, and model of cerebral blast injury was established. After injury, routine CT, magnetic resonance imaging (MRI), DWI and DTI were performed, and quantified analysis of region of interest was conducted with Functool 2 postprocessing technology. The cerebral histopathological changes were observed, and contrast analysis was carried out with findings from DWI and DTI of the same plane. Results Of the 30 rabbits, there was no abnormal cerebral imaging findings in 6 rabbits by CT, T1WI and T2WI, and there was no abnormal low signal in 2 of the 6 rabbits by DWI. Among the other 24 rabbits, CT only revealed pneumatosis in brain, MRI routine subsequence demonstrated non-hemorrhagic foci, which were characterised by low or slightly lower signal on T1WI and high signal on T2WI, and DWI indicated bright-white high signal. DWI illustrated 189 non-hemorrhagic foci, which exhibited punctiform (28.5%), lamellar (54.0%) and slinar (17.5%) high signal, with sharp border. The number of non-hemorrhagic foci detected by DWI was significantly larger than those revealed by conventional T1WI and T2WI (P<0.01). DTI demonstrated decrease in apparent diffusion coefficient (ADC) and fiber tractography (FA) of region of interest, especially for the inner capsule (P<0.01). There was linear correlation of decrease in ADC and FA values of cerebral white matter and brain stem with time of survival of rabbits (r=0.53,P=0.05;r=0.13,P=0.03;r=0.25,P=0.04;r=0.27,P=0.02). Conclusion DWI may provide higher detection rate for non-hemorrhagic foci in rabbits with cerebral blast injury, especially for small lamellar non-hemorrhagic foci. DTI may play a role in outcome prediction through measurement of decrease in ADC and FA values.

Key words: blast injury, diffusion weighted imaging, diffusion tensor imaging, magnetic resonance imaging