弥散张量成像在颅脑损伤昏迷病人中的应用

TApplication of diffusion tensor imaging in patients with coma after traumatic brain injury

摘要:

目的 初步探讨颅脑损伤昏迷病人上行网状激活系统（ARAS）弥散张量成像（DTI）和预后的相关性。方法 以最近3年的颅脑损伤后昏迷病人为研究对象，在颅脑创伤后的3周和5周行DTI和纤维示踪成像（DTT）检查。种子兴趣区为中脑和桥脑被盖区，目标兴趣区为丘脑板内核。分析ARAS纤维束的部分各向异性（FA）、平均弥散率（MD）、纤维束量（TV），及其变异和病人颅脑创伤3月后意识状态的关系。采用Spearman相关分析，分析FA、MD、TV和预后评分的相关性。结果 3周时上行网状激动系统FA、MD和3月时的预后之间无相关性，TV和3月时的预后有统计学相关性（相关系数为0.89，P<0.001）。5周时，FA、TV和3月时的预后呈正相关性（P<0.001），3周至5周间FA的变异与3月时的GCS评分和GOS评分呈正相关（P<0.005，P<0.05），TV变异和3月时GCS评分和GOS评分呈正相关（P<0.001）。结论 颅脑损伤后昏迷患者3月后的意识状态和DTI所模拟颅脑损伤后5周时ARAS的FA、MD、TV及动态变化有相关性。亚急性期上行网状激动系统纤维束的改变可以间接反映患者意识恢复能力。

Abstract:

Objective To preliminarily investigate the correlation between diffusion tensor imaging (DTI) parameters of the ascending reticular activating system (ARAS) and prognosis in patient with coma after traumatic brain injury (TBI).Methods Patients with coma after TBI in the last three years were selected as research subjects. DTI and diffusion tensor tractography of the ARAS were performed at 3 and 5 weeks after TBI. Two regions of interest (ROIs) for reconstruction of the ARAS were the seed ROIs-the midbrain and the tegmental region of the pons and the target ROI-the thalamic intralaminar nuclei. The fractional anisotropy (FA), mean diffusivity (MD), and tract volume (TV) of the ARAS fiber tracts were systematically analyzed and the correlation between the changes of ARAS fiber tracts and the consciousness status of the patients at 3 months after TBI was analyzed. A Spearman correlation analysis was used to analyze the correlation between FA, MD, and TV and prognostic score.Results There was no correlation between the FA and MD of the ARAS at 3 weeks after TBI and the prognosis at 3 months after TBI (P>0.05), while there was a significant correlation between the TV of the ARAS at 3 weeks after TBI and the prognosis at 3 months after TBI (r=0.89,P<0.001). The prognosis at 3 months after TBI was positively correlated with the FA and TV of the ARAS at 5 weeks after TBI (P<0.001;P<0.001). The Glasgow Coma Scale score and Glasgow Outcome Scale score at 3 months after TBI were positively correlated with the changes in FA and TV from 3 to 5 weeks after TBI (P<0.005;P<0.05;P<0.001;P<0.001).Conclusions The consciousness status of patients with coma at 3 months after TBI is correlated with the DTI simulated FA, MD, and TV of the ARAS and their changes at 5 weeks after TBI. The changes of the ARAS fiber tracts in subacute phase can indirectly reflect patients' ability to recover consciousness.