Kim Junghoon, Avants Brian, Patel Sunil, Whyte John, Coslett Branch H, Pluta John, Detre John A, Gee James C
Moss Rehabilitation Research Institute, Albert Einstein Healthcare Network, Philadelphia, PA 19141, USA.
Neuroimage. 2008 Feb 1;39(3):1014-26. doi: 10.1016/j.neuroimage.2007.10.005. Epub 2007 Oct 13.
Traumatic brain injury (TBI) is one of the most common causes of long-term disability. Despite the importance of identifying neuropathology in individuals with chronic TBI, methodological challenges posed at the stage of inter-subject image registration have hampered previous voxel-based MRI studies from providing a clear pattern of structural atrophy after TBI. We used a novel symmetric diffeomorphic image normalization method to conduct a tensor-based morphometry (TBM) study of TBI. The key advantage of this method is that it simultaneously estimates an optimal template brain and topology preserving deformations between this template and individual subject brains. Detailed patterns of atrophies are then revealed by statistically contrasting control and subject deformations to the template space. Participants were 29 survivors of TBI and 20 control subjects who were matched in terms of age, gender, education, and ethnicity. Localized volume losses were found most prominently in white matter regions and the subcortical nuclei including the thalamus, the midbrain, the corpus callosum, the mid- and posterior cingulate cortices, and the caudate. Significant voxel-wise volume loss clusters were also detected in the cerebellum and the frontal/temporal neocortices. Volume enlargements were identified largely in ventricular regions. A similar pattern of results was observed in a subgroup analysis where we restricted our analysis to the 17 TBI participants who had no macroscopic focal lesions (total lesion volume >1.5 cm(3)). The current study confirms, extends, and partly challenges previous structural MRI studies in chronic TBI. By demonstrating that a large deformation image registration technique can be successfully combined with TBM to identify TBI-induced diffuse structural changes with greater precision, our approach is expected to increase the sensitivity of future studies examining brain-behavior relationships in the TBI population.
创伤性脑损伤（TBI）是导致长期残疾的最常见原因之一。尽管识别慢性创伤性脑损伤患者的神经病理学很重要，但在个体间图像配准阶段所面临的方法学挑战阻碍了以往基于体素的MRI研究明确创伤性脑损伤后结构萎缩的模式。我们使用一种新型的对称微分同胚图像归一化方法对创伤性脑损伤进行基于张量的形态学测量（TBM）研究。该方法的关键优势在于它能同时估计一个最优的模板脑以及该模板与个体受试者脑之间的拓扑保持变形。然后通过将对照组和受试者的变形与模板空间进行统计学对比，揭示萎缩的详细模式。参与者包括29名创伤性脑损伤幸存者和20名在年龄、性别、教育程度和种族方面相匹配的对照受试者。局部体积损失最显著地出现在白质区域以及包括丘脑、中脑、胼胝体、扣带回中部和后部以及尾状核在内的皮质下核团。在小脑以及额叶/颞叶新皮质中也检测到了显著的体素水平体积损失簇。体积增大主要在脑室区域被发现。在一项亚组分析中观察到了类似的结果模式，在该分析中我们将分析限制在17名没有宏观局灶性病变（总病变体积>1.5 cm³）的创伤性脑损伤参与者中。当前研究证实、扩展并部分挑战了以往关于慢性创伤性脑损伤的结构MRI研究。通过证明一种大变形图像配准技术可以成功地与TBM相结合，以更高的精度识别创伤性脑损伤引起的弥漫性结构变化，我们的方法有望提高未来研究在创伤性脑损伤人群中检查脑 - 行为关系的敏感性。
