Cui Jiao-Long, Li Xiang, Chan Tin-Yan, Mak Kin-Cheung, Luk Keith Dip-Kei, Hu Yong
Department of Orthopaedics and Traumatology, The University of Hong Kong, 12 Sandy Bay Road, Pokfulam, Hong Kong.
Eur Spine J. 2015 Jan;24(1):41-7. doi: 10.1007/s00586-014-3522-5. Epub 2014 Aug 24.
Cervical spondylotic myelopathy (CSM) is a common spinal cord disorder in the elderly. Diffusion tensor imaging (DTI) has been shown to be of great value for evaluating the microstructure of nerve tracts in the spinal cord. Currently, the quantitative assessment of the degeneration on the specific tracts in CSM is still rare. The aim of the present study was to use tractography-based quantification to investigate the column-specific degeneration in CSM.
A total of 43 volunteers were recruited with written informed consent, including 20 healthy subjects and 23 CSM patients. Diffusion MRI was taken by 3T MRI scanner. Fiber tractography was performed using TrackVis to reconstruct the white matter tracts of the anterior, lateral and posterior column on the bilateral sides. The DTI metrics acquired from tractography, including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity (RD), were compared between healthy subjects and CSM patients.
Compared to healthy subjects, FA was found significantly lower in the lateral (Healthy 0.64 ± 0.07 vs. CSM 0.53 ± 0.08) and posterior column (Healthy 0.67 ± 0.08 vs. CSM 0.47 ± 0.08) (p < 0.001), while MD, AD and RD were significantly higher in the anterior, lateral and posterior column in CSM (p < 0.05).
Loss of microstructural integrity was detected in the lateral and posterior column in CSM. Tractography-based quantification was capable of evaluating the subtle pathological insult within white matter on a column-specific basis, which exhibited potential clinical value for in vivo evaluation of the severity of CSM.
脊髓型颈椎病（CSM）是老年人常见的脊髓疾病。弥散张量成像（DTI）已被证明在评估脊髓神经纤维束微观结构方面具有重要价值。目前，对CSM中特定神经纤维束退变的定量评估仍然较少。本研究的目的是使用基于纤维束成像的定量分析来研究CSM中柱特异性退变情况。
共招募43名签署书面知情同意书的志愿者，包括20名健康受试者和23名CSM患者。使用3T MRI扫描仪进行弥散MRI检查。使用TrackVis软件进行纤维束成像，重建双侧前柱、侧柱和后柱的白质纤维束。比较健康受试者和CSM患者在纤维束成像中获得的DTI参数，包括各向异性分数（FA）、平均扩散率（MD）、轴向扩散率（AD）和径向扩散率（RD）。
与健康受试者相比，CSM患者侧柱（健康组0.64±0.07 vs. CSM组0.53±0.08）和后柱（健康组0.67±0.08 vs. CSM组0.47±0.08）的FA显著降低（p<0.001），而CSM患者前柱、侧柱和后柱的MD、AD和RD显著升高（p<0.05）。
CSM患者侧柱和后柱存在微观结构完整性丧失。基于纤维束成像的定量分析能够在柱特异性基础上评估白质内的细微病理损伤，这在体内评估CSM严重程度方面具有潜在临床价值。
