扩散张量成像在脑外伤严重程度评估中的应用价值

摘要

目的 探讨扩散张量成像(diffusion tensor imaging,DTI)在脑外伤诊断与严重程度评估中的应用价值.方法收集轻型、中型、重型脑外伤患者及正常志愿者各20例,行MRI平扫、DTI扫描并进行格拉斯哥昏迷评分(Glasgow coma scale,GCS).于胼胝体、扣带束等共27个脑白质区域内勾画感兴趣区(region of interest, ROI),并记录各向异性分数(fractional anisotropy,FA)值.对正常对照组、轻型、中型、重型脑外伤组四组间各个区域的FA值数据分别进行多组间比较,并采用相应检验方法进行两两比较,以P <0.05为差异具有统计学意义.对患者的GCS与各个区域的FA值分别行相关性分析,以P <0.05为两者间具有相关性.结果 对正常对照组、轻型、中型、重型脑外伤组各区域FA值之间进行比较,胼胝体膝、体、压部、双侧扣带束、双侧半卵圆中心等25个区域,四组间FA值的差异具有统计学意义( P <0.05).进一步对四组间进行两两比较,正常与轻型、正常与中型、正常与重型、轻型与中型、轻型与重型、中型与重型组间FA值差异具有统计学意义的区域分别为14个、20个、25个、5个、23个、17个,其中以正常与重型、轻型与重型组间有差异的区域数为最多,轻型与中型间最少.胼胝体膝、体、压部、双侧扣带束等共26个区域的FA值与患者GCS间存在正相关性.其中,以右侧扣带束的相关系数为最大( r =0.872).结论 DTI序列在脑外伤的诊断及严重程度评估中具有重要的临床应用价值.%Objective To evaluate the utility of DTI in the evaluation of the TBI severity. Methods Mild,moderate and se-vere TBI patients(20 respectively),and 20 healthy volunteers were collected. All patients underwent conventional MRI,DTI and GCS assessment. ROI of 27 brain regions were outlined and the FA values were recorded. For FA values of each ROI, statistic comparisons among the four groups were made,then pairwise comparison was processed by corresponding test methods. The corre-lation analysis between GCS scores and FA values of each region were performed. P <0.05 was considered statistically signifi-cant. Results Totally,25 regions(the corpus callosum,bilateral cingulate bundle,bilateral centrum semiovale,etc.) differed in FA values between the four groups ( P <0.05). Further, the result of pairwise comparisons among the four groups showed that:for volunteer and mild,volunteer and moderate,volunteer and severe,mild and moderate,mild and severe, moderate and severe,the number of regions that the FA values got statistical significance were 14,20,25,5,23,17,respectively. For totally 26 regions,for exmaple,the corpus callosum and bilateral cingulate bundle,the FA values got positive correlation with the GCS scores. Wherein,the correlation coefficient of the right cingulum was maximum( r =0.872). Conclusion The clinical applica-tions of DTI in diagnosing and evaluating the TBI severity is of great significance.