Department of Neuroscience, Norwegian University of Science and Technology (NTNU), Trondheim N-7489, Norway.
J Neurol Neurosurg Psychiatry. 2012 Dec;83(12):1193-200. doi: 10.1136/jnnp-2012-302644. Epub 2012 Aug 29.
To study the evolution of traumatic axonal injury (TAI) detected by structural MRI in patients with moderate and severe traumatic brain injury (TBI) during the first year and relate findings to outcome.
58 patients with TBI (Glasgow Coma Scale score 3-13) were examined with MRI at a median of 7 days, 3 months and 12 months post injury. TAI lesions were evaluated blinded and categorised into three stages based on location: hemispheres, corpus callosum and brainstem. Lesions in T2* weighted gradient echo (GRE), fluid attenuated inversion recovery (FLAIR) and diffusion weighted imaging (DWI) were counted and FLAIR lesion volumes were estimated. Inter-rater reliability score was calculated. Outcome was assessed 12 months post injury using the Glasgow Outcome Scale Extended.
In the initial MRI, 31% had brainstem lesions compared with 17% at 3 months (p=0.008). In the FLAIR sequences, number and volumes of lesions were reduced from early to 3 months (p<0.001). In T2*GRE sequences, the number of lesions persisted at 3 months but was reduced at 12 months (p=0.007). The number of lesions in DWI and volume of FLAIR lesions on early MRI predicted worse clinical outcome in adjusted analyses (p<0.05).
This is the first study to demonstrate and quantify attenuation of non-haemorrhagic TAI lesions on structural MRI during the first 3 months after TBI; most importantly, the disappearance of brainstem lesions. Haemorrhagic TAI lesions attenuate first after 3 months. Only early MRI findings predicted clinical outcome after adjustment for other prognostic factors. Hence valuable clinical information may be missed if MRI is performed too late after TBI.
研究中重度创伤性脑损伤（TBI）患者在伤后 1 年内结构 MRI 检测到的创伤性轴索损伤（TAI）的演变，并将发现结果与预后相关联。
对 58 例 TBI 患者（格拉斯哥昏迷量表评分 3-13）进行 MRI 检查，中位数时间分别为伤后 7 天、3 个月和 12 个月。TAI 病变采用盲法评估，并根据病变部位分为 3 期：半球、胼胝体和脑干。对 T2*加权梯度回波（GRE）、液体衰减反转恢复（FLAIR）和弥散加权成像（DWI）中的病变进行计数，并估计 FLAIR 病变体积。计算组内相关系数评分。使用格拉斯哥结局量表扩展版评估伤后 12 个月的预后。
在初始 MRI 中，31%的患者存在脑干病变，而在 3 个月时为 17%（p=0.008）。在 FLAIR 序列中，病变数量和体积从早期到 3 个月减少（p<0.001）。在 T2*GRE 序列中，病变数量在 3 个月时保持不变，但在 12 个月时减少（p=0.007）。早期 MRI 中病变的数量和 FLAIR 病变的体积预测调整后临床结局较差（p<0.05）。
这是第一项研究，证明并量化了 TBI 后前 3 个月结构 MRI 中非出血性 TAI 病变的衰减；最重要的是，脑干病变的消失。出血性 TAI 病变在 3 个月后首先衰减。只有早期 MRI 发现调整其他预后因素后才能预测临床结局。因此，如果 MRI 在 TBI 后进行得太晚，可能会错过有价值的临床信息。
