Holly Langston T, Freitas Bonnie, McArthur David L, Salamon Noriko
Departments of Neurosurgery, David Geffen School of Medicine at the University of California at Los Angeles, California 90095, USA.
J Neurosurg Spine. 2009 Mar;10(3):194-200. doi: 10.3171/2008.12.SPINE08367.
Magnetic resonance spectroscopy is commonly used to provide cellular and metabolic information in the management of a variety of pathological processes that affect the brain, and its application recently has been expanded to the cervical spine. The majority of radiographic investigations into the pathophysiology of cervical spondylotic myelopathy (CSM) have been focused on the spinal cord macrostructure. The authors sought to determine the feasibility of using MR spectroscopy to analyze spinal cord biochemical function in patients with CSM.
Twenty-one patients with clinical and radiographic evidence of CSM were prospectively enrolled in this study. The patients underwent preoperative neurological examination, functional assessment, and cervical spine MR spectroscopy. Voxels were placed at the C-2 level, and the MR spectroscopy spectra peaks for N-acetylaspartate (NAA), choline, lactate (Lac), and creatine (Cr) were measured. Thirteen age-matched healthy volunteers served as controls.
The NAA/Cr ratio was significantly lower in patients with CSM than in controls (1.27 vs 1.83, respectively, p < 0.0001). The choline/Cr ratio was not significantly different between the 2 groups. Seven of the patients with CSM had a Lac peak, whereas no peaks were noted in the control group (p < 0.05). There was no correlation between the severity of myelopathy and the NAA/Cr ratio in the CSM cohort.
Data in this study demonstrated the feasibility of using MR spectroscopy to evaluate the cellular biochemistry of the spinal cord in patients with CSM. Patients with CSM had a significantly lower NAA/Cr ratio than healthy controls, likely because of axonal and neuronal loss. The presence of Lac peaks in one-third of the patients in the CSM cohort further supports the role of ischemia in the pathophysiology of CSM.
磁共振波谱常用于为影响大脑的各种病理过程的管理提供细胞和代谢信息，其应用最近已扩展到颈椎。大多数关于脊髓型颈椎病（CSM）病理生理学的影像学研究都集中在脊髓的宏观结构上。作者试图确定使用磁共振波谱分析CSM患者脊髓生化功能的可行性。
本研究前瞻性纳入了21例有CSM临床和影像学证据的患者。患者接受了术前神经学检查、功能评估和颈椎磁共振波谱检查。在C-2水平放置体素，并测量N-乙酰天门冬氨酸（NAA）、胆碱、乳酸（Lac）和肌酸（Cr）的磁共振波谱峰。13名年龄匹配的健康志愿者作为对照。
CSM患者的NAA/Cr比值显著低于对照组（分别为1.27和1.83，p<0.0001）。两组之间的胆碱/Cr比值无显著差异。7例CSM患者有Lac峰，而对照组未发现峰（p<0.05）。CSM队列中脊髓病的严重程度与NAA/Cr比值之间无相关性。
本研究数据证明了使用磁共振波谱评估CSM患者脊髓细胞生物化学的可行性。CSM患者的NAA/Cr比值显著低于健康对照组，可能是由于轴突和神经元丢失。CSM队列中三分之一的患者出现Lac峰，进一步支持了缺血在CSM病理生理学中的作用。
