Kumar Raj, Husain Mazhar, Gupta Rakesh K, Hasan Khader M, Haris Mohammad, Agarwal Atul K, Pandey C M, Narayana Ponnada A
Department of Neurosurgery, Chhatrapati Shahuji Maharaj Medical University, UP, India.
J Neurotrauma. 2009 Apr;26(4):481-95. doi: 10.1089/neu.2008.0461.
Diffuse axonal injury (DAI) that follows traumatic brain injury (TBI) is thought to be a major contributor to neurocognitive dysfunction that sometimes follows TBI. Conventional magnetic resonance imaging (MRI), diffusion tensor imaging (DTI) and neuropsychological tests (NPT) were performed on 38 TBI patients [hemorrhagic DAI (H-DAI, n=8), non-hemorrhagic (Nh-DAI, n=7), with no apparent DAI on conventional MRI (NA-DAI, n=23)] with a Glasgow Coma Scale score ranging between 9 and 13. The fractional anisotropy (FA) and mean diffusivity (MD) were quantified from different regions of the corpus callosum (CC), and peri-ventricular white matter (PWM) within 5-14 days and 6 months following TBI. Patients in all three groups showed decreased FA in the anterior limb of the internal capsule (ALIC) and the posterior limb of the internal capsule (PLIC), while the genu of the CC showed a decrease in the H-DAI group during the early period following TBI that persisted 6 months later, which appeared to be consistent with axonopathy. In patients without abnormalities on conventional MRI and DTI in the initial phase, a significant decrease in FA and increase in MD were observed in a few regions of the CC at 6 months, which was suggestive of demyelination/gliosis. The changes in FA and MD in the CC and PWM at 6 months follow-up showed significant correlation with some of the NPT performed in the three groups. DTI demonstrates axonopathy in the acute stage, as well as at secondary stages, at 6 months post-injury in the CC and PWM in regions of normal-appearing white matter on conventional MRI.
创伤性脑损伤（TBI）后发生的弥漫性轴索损伤（DAI）被认为是TBI后有时会出现的神经认知功能障碍的主要原因。对38例格拉斯哥昏迷量表评分为9至13分的TBI患者进行了常规磁共振成像（MRI）、扩散张量成像（DTI）和神经心理学测试（NPT）[出血性DAI（H-DAI，n = 8）、非出血性（Nh-DAI，n = 7）、常规MRI上无明显DAI（NA-DAI，n = 23）]。在TBI后的5 - 14天和6个月内，从胼胝体（CC）的不同区域以及脑室周围白质（PWM）中量化分数各向异性（FA）和平均扩散率（MD）。所有三组患者的内囊前肢（ALIC）和内囊后肢（PLIC）的FA均降低，而CC膝部在TBI后的早期H-DAI组出现降低，并持续至6个月后，这似乎与轴索性病变一致。在初始阶段常规MRI和DTI无异常的患者中，6个月时在CC的一些区域观察到FA显著降低和MD增加，提示存在脱髓鞘/胶质增生。6个月随访时CC和PWM中FA和MD的变化与三组中进行的一些NPT显著相关。DTI显示在急性期以及损伤后6个月的继发阶段，在常规MRI上外观正常的白质区域的CC和PWM中存在轴索性病变。
