磁共振弥散张量成像在创伤性脑损伤诊断中的应用

目的 评估磁共振弥散张量成像（DTI）对创伤性脑损伤（TBI）的诊断价值。方法 应用常规磁共振扫描及DTI对22例TBI患者(伤后1～7 d)和14名健康志愿者（对照组）进行检查。行DTI图像后处理得到不同兴趣区（ROI）各向异性分数（FA），包括两侧内囊膝和后肢、胼胝体膝和压部的FA值。比较两组相同ROI的FA值，并比较TBI组患侧与健侧对称ROI的FA值。对TBI组FA值与格拉斯哥昏迷评分（GCS）进行Pearson直线相关分析。结果 与对照组比较，TBI组各ROI的FA值均下降，差异有统计学意义（P<0.01）；与健侧对称ROI比较，TBI组患侧的FA值明显降低（P<0.01）；TBI组各部位的FA值与GCS无明显相关性（P>0.01）。结论 DTI技术对白质纤维损伤较为敏感，能准确定量分析损伤程度，可为临床TBI患者的早期确诊提供依据。

Application of MRI diffusion tensor imaging on diagnosis of traumatic brain injury

Objective To evaluate the value of MRI diffusion tensor imaging (DTI) on diagnosis of traumatic brain injury(TBI). Methods Twenty two patients with TBI 1 to 7 days post-injury and 14 healthy controls were studied with DTI and conventional MRI. The fractional anisotropy (FA) was quantified from different regions of interest (ROI) including the genu of corpus callosum (CC), the splenium of CC, the genu of internal capsule (IC) and the posterior limb of IC bilaterally. The FA value of the same ROI was compared between TBI group and control group, and FA value of the lesion side was compared with the mirror healthy side in TBI group. Correlations between the FA and Glasgow coma scale (GCS) in TBI patients were analyzed with Pearson linear correlation. Results Compared with control group, the FA value decreased significantly in each ROI (P<0.01). Compared with the healthy side, FA value was also significantly lower in lesion side in TBI group (P<0.01). The FA value in all the sites were not correlated with GCS in TBI group (P>0.01).Conclusion DTI is sensitive for detecting the acute traumatic injury of white matter and evaluate the degree of injury. It offers the possibility to diagnose TBI earlier and accurately.