轻中型颅脑损伤后认知功能障碍的DTI研究

目的应用弥散张量成像(diffusion tensor imaging,DTI)技术探讨轻中型颅脑损伤病人不同部位脑白质微结构改变与其认知功能障碍的相关性。方法分析127例轻中型颅脑损伤病人的临床资料,伤后10 d采用蒙特利尔认知评估量表(Mo CA)评定有无认知功能障碍,并常规行头颅MRI检查,采集DTI数据,测量两侧额叶、颞叶内侧、顶叶,胼胝体膝部和压部,中脑部位的感兴趣区各向异性分数(FA值)、表观弥散系数(ADC值),并与Mo CA评估结果进行相关性分析。结果以Mo CA量表为标准评定,无认知功能障碍41例(32.28%,无认知障碍组),存在认知功能障碍86例(67.72%,认知障碍组),主要表现为视空间与执行功能、注意力和计算力、语言、抽象能力、延迟记忆的障碍。与无认知障碍的病人相比,认知障碍的病人两侧额叶、颞叶内侧、胼胝体膝部FA值降低,ADC值增加,差异具有统计学意义(P0.01)。结论轻中型颅脑损伤病人早期存在显著认知功能障碍,以视空间与执行功能、注意力和计算力、语言、抽象能力、延迟记忆障碍为主。颅脑损伤后早期认知功能障碍与病人额叶、颞叶、胼胝体白质受损密切相关。

Diffusion tensor imaging for cognitive dysfunction after mild-moderate traumatic brain injury

Objective To explore the relevance of the microstructural changes at different sites in the white matter to cognitive dysfunction using diffusion tensor imaging （DTI） in mild-moderate traumatic brain injury （TBI） patients. Methods The clinical data of 127 patients with TBI were analyzed. The cognitive dysfunction was evaluated by Montreal Cognitive Assessment （MoCA） after 10 days post injury. The MRI and DTI scans were used to obtain the fractional anisotropy （FA） and apparent diffusion coefficient （ADC） in following regions of interest： the bilateral frontal, mesial temporal, and parietal lobes, genu and splenium part of the corpus callosum and mid-brain. The correlation between DTI and the MoCA was analyzed. Results According to MoCA standard assessment, non-cognitive dysfunction was seen in 41 cases （32.28%） and cognitive dysfunction in 86 （67.72%）. Cognitive dysfunction manifested mainly as disorders of visual-spatial and executive function, attention and calculation ability, language, abstract ability, delayed memory. There were more significant decrease of FA values and increase of ADC values in bilateral frontal lobes, mesial temporal lobe and genu part of corpus callosum in the patients with cognitive impairment than in those without cognitive impairment （P 〈 0.01）. Conclusions Cognitive dysfunction is common in early stage of mild-moderate TBI, with being dominated by the disorders of visual-spatial and executive function, attention and calculation ability, language, abstract ability, delayed memory, and closely associated with microstructural damage in the frontal lobe, temporal lobe and corpus callosum.