创伤性脑损伤后脑白质损伤与认知功能障碍的相关性研究

Correlation study of cerebral white matter lesion with cognitive dysfunction after traumatic brain injury

目的利用磁共振张量成像（DTI）分析创伤性颅脑损伤（TBI）后脑白质各个参数值的变化与认知功能障碍有无相关性。方法选取2012年10月-2013年9月收治的TBI患者17例，按照格拉斯哥昏迷评分（GCS）分为≥13分组（轻度组，10例）和≤12分组（中重度组，7例）。另选取17例健康志愿者作为对照组。均行磁共振张量成像（DTI）检查，并使用Neuro3D软件测量胼胝体膝部、胼胝体压部、内囊后肢、内囊前肢及大脑脚的各向异性分数（FA）及表观扩散系数（ADC）值，比较各组FA及ADC值之间的差异。每例患者按照简易精神状态检查（MMSE）标准进行检查评分，比较分析研究组FA及ADC值与MMSE有无相关性。结果与对照组比较，中重度组胼胝体膝部及压部FA值明显降低，胼胝体膝部及压部、内囊后肢及大脑脚ADC值升高（P〈0．05或0．01）。轻度组各兴趣区域FA及ADC值差异无统计学意义（P〉0．05）。MMSE与胼胝体膝部及压部的FA呈正相关（r分别为0．636，0．601），与胼胝体膝部及压部ADC值呈负相关（r分别为0．552、0．660），FA降低越明显和ADC值升高越明显，MMSE值降低越明显。结论DTI可以发现CT及常规MRI无法显示的脑白质病变，有助于评估TBI患者认知功能损害程度，为治疗及预后提供客观依据。

Objective To analyze the correlation between white matter injury and cognitive dysfunction using diffusion tensor imaging （DTI）. Methods Seventeen subjects with TBI hospitalized from October 2012 to September 2013 had Glasgow coma scale （GCS） score of ≥ 13 （ mild injury group, l0 cases） and ≤ 12. （moderate-severe iujury group, 7 cases）. Another 17 healthy subjects were used as controls. All were submitted to DTI examination. Fractional anisotropy （FA） and apparent diffusion coefficient（ ADC ） values in genu corpus callosum, splenium corpus callosum, posterior internal capsule, anterior internal capsule, and cerebral peduncle were calculated using the Neuro 3D software. Correlations between FA and ADC with the mini-mental state examination （MMSE） score were evaluated. Results Moderate-severe injury group demonstrated significantly reduced FA values in genu corpus callosum and splenium corpus callosum, and significantly increased ADC values of genu corpus callosum, splenium corpus callosum, posterior internal capsule and cerebral peduncle when compared to control group （P〈0.05 or 0.01 ）. FA and ADC values in the regions of interest did not differ significantly between mild injury group and control group （P 〉 0. 05）. In the genu corpus callosum and splenium corpus callosum, FA values were positively correlated with MMSE score （ r = 0.636, 0. 601 ）, while ADC values were negatively correlated with MMSE score （ r = 0. 552, 0. 660 ）. Conclusions DTI reveals the cerebral white matter lesion that is undetectable using CT and conventional MRI. DTI is a helpful tool to evaluate the degree of cognitive function in patients with TBI, which provides the basic reference for the clinical treatment and prognosis.