Kobayashi Shigeru, Suzuki Yoshihiko, Meir Adam, Al-Khudairi Naji, Nakane Takashi, Hayakawa Katsuhiko
Department of Orthopaedics and Rehabilitation Medicine, Faculty of Medicine, University of Fukui, 23-3, Shimoaizuki, Matsuoka, Eiheiji, Fukui 910-1193, Japan; Research and Education Program for Life Science, University of Fukui, Fukui, Japan.
Suzuki Orthopaedic Clinic, 5-1, Tokiguchi, Nakamati, Toki, Gifu, 509-5124, Japan.
Spine J. 2015 Oct 1;15(10):2132-41. doi: 10.1016/j.spinee.2015.05.014. Epub 2015 May 18.
There has been no study regarding the cauda equina circulation of patients with neurogenic intermittent claudication (NIC) in lumbar spinal canal stenosis (LSCS) using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI).
The mechanism responsible for the onset of NIC was investigated using DCE-MRI to examine changes in cauda equina blood flow in patients with LSCS.
This was a retrospective longitudinal registry and magnetic resonance imaging study.
The subjects consisted of 23 patients who had LSCS associated with NIC (stenosis group). Ten asymptomatic volunteers who did not have NIC served as controls (control group). In the LSCS group, the cross-sectional area of the dural sac was <75 mm2 at the site of most severe stenosis. These patients were further divided into single and double stenosis subgroups.
The main measures we used were the signal intensity (S-I) ratio and the shape and size of the time intensity (T-I) curves. We compared these between the stenosis and control groups.
At first, plain T1-weighted MR images were obtained and the lumbar dural sac cross-sectional area was measured using a digitizer. For DCE-MRI, sagittal T1-weighted images of the same slice were acquired continuously for 10 minutes after administration of gadolinium as an intravenous bolus to observe the distribution of contrast medium (gadolinium) in the cauda equina. To objectively evaluate changes in contrast enhancement of the cauda equina at the site of canal stenosis, regions of interest were established. The signal intensity (SI) ratio was calculated to compare the signal intensities before and after contrast enhancement, and time-intensity curves were prepared to investigate changes over time.
The static imaging findings and the changes of gadolinium uptake showed striking differences between the study and control patients. In the stenosis group, abnormal intrathecal enhancement showed around the site of stenosis on enhanced MR imaging. The SI ratio at the site of canal stenosis had a slower increase in the arterial phase when compared with that in the control group and remained high in the venous phase for up to 10 minutes. Finally, abnormal intrathecal enhancement was visible around the site of stenosis on enhanced MR imaging in all patients.
These clinical data indicate that cauda equina nerve roots in the LSCS patients are pathologic even when symptoms are not elicited in the supine position, suggesting that intraradicular venous congestion and edema themselves do not influence the existence of radicular symptoms.
尚无关于使用动态对比增强磁共振成像（DCE-MRI）对腰椎管狭窄症（LSCS）合并神经源性间歇性跛行（NIC）患者马尾神经循环的研究。
使用DCE-MRI研究LSCS患者马尾神经血流变化，以探究NIC发病机制。
这是一项回顾性纵向登记和磁共振成像研究。
研究对象包括23例患有与NIC相关的LSCS患者（狭窄组）。10名无NIC的无症状志愿者作为对照组（对照组）。在LSCS组中，硬脊膜囊在最严重狭窄部位的横截面积<75 mm²。这些患者进一步分为单节段和双节段狭窄亚组。
我们使用的主要指标是信号强度（S-I）比值以及时间-强度（T-I）曲线的形状和大小。我们在狭窄组和对照组之间进行了比较。
首先，获取T1加权平扫磁共振图像，并使用数字化仪测量腰椎硬脊膜囊横截面积。对于DCE-MRI，静脉注射钆对比剂后，在同一层面连续采集矢状位T1加权图像10分钟，以观察钆对比剂在马尾神经中的分布。为客观评估椎管狭窄部位马尾神经对比增强的变化，设定感兴趣区。计算信号强度（SI）比值以比较对比增强前后的信号强度，并绘制时间-强度曲线以研究随时间的变化。
研究患者与对照患者在静态成像结果和钆摄取变化方面存在显著差异。在狭窄组中，增强磁共振成像显示狭窄部位周围鞘内异常强化。与对照组相比，椎管狭窄部位的SI比值在动脉期升高较慢，在静脉期持续10分钟保持较高水平。最后，所有患者增强磁共振成像均显示狭窄部位周围鞘内异常强化。
这些临床数据表明，即使在仰卧位未引发症状时，LSCS患者的马尾神经根也已发生病理改变，提示神经根内静脉充血和水肿本身并不影响神经根性症状的存在。
