Kim Joong Hee, Loy David N, Liang Hsiao-Fang, Trinkaus Kathryn, Schmidt Robert E, Song Sheng-Kwei
Department of Radiology, Washington University, St. Louis, Missouri 63110, USA.
Magn Reson Med. 2007 Aug;58(2):253-60. doi: 10.1002/mrm.21316.
We examined in vivo measurements of directional diffusivity derived from diffusion tensor imaging (DTI) to study the evolution of ventrolateral white matter (VWM) changes following contusive spinal cord injury (SCI) in C57BL/6 mice at 1, 3, 7, and 14 days postinjury. Relative anisotropy maps provided excellent gray matter (GM)/white matter (WM) contrast for characterization of evolving WM injury at all time points. Longitudinal DTI measurements clearly demonstrated rostral-caudal injury asymmetry. Axial diffusivity provided a sensitive, noninvasive measure of axonal integrity within the injury epicenter and at remote levels. Quantitative measurements of axial and radial diffusivities in VWM showed a trend of acute primary axonal injury followed by delayed, subacute myelin damage at the impact site, with good histological correlation.
我们通过扩散张量成像（DTI）对方向扩散率进行了体内测量，以研究C57BL/6小鼠在挫伤性脊髓损伤（SCI）后1、3、7和14天腹外侧白质（VWM）变化的演变情况。相对各向异性图在所有时间点都为表征不断演变的白质损伤提供了出色的灰质（GM）/白质（WM）对比度。纵向DTI测量清楚地显示了头-尾损伤不对称性。轴向扩散率为损伤中心及其远端水平的轴突完整性提供了一种敏感的、非侵入性测量方法。VWM中轴向和径向扩散率的定量测量显示，在撞击部位存在急性原发性轴突损伤，随后是延迟性、亚急性髓鞘损伤的趋势，且与组织学有良好的相关性。
