Continuum (Minneap Minn). 2021 Feb 1;27(1):225-263. doi: 10.1212/CON.0000000000000926.
This article reviews the neuroimaging of disorders of the spinal cord and cauda equina, with a focus on MRI. An anatomic approach is used; diseases of the extradural, intradural-extramedullary, and intramedullary (parenchymal) compartments are considered, and both neoplastic and non-neoplastic conditions are covered. Differentiating imaging features are highlighted.
Although T2-hyperintense signal abnormality of the spinal cord can have myriad etiologies, neuroimaging can provide specific diagnoses or considerably narrow the differential diagnosis in many cases. Intradural-extramedullary lesions compressing the spinal cord have a limited differential diagnosis and are usually benign; meningiomas and schwannomas are most common. Extradural lesions can often be specifically diagnosed. Disk herniations are the most commonly encountered mass of the epidural space. Cervical spondylotic myelopathy can cause a characteristic pattern of enhancement, which may be mistaken for an intrinsic myelopathy. A do-not-miss diagnosis of the extradural compartment is idiopathic spinal cord herniation, the appearance of which can overlap with arachnoid cysts and webs. Regarding intrinsic causes of myelopathy, the lesions of multiple sclerosis are characteristically short segment but can be confluent when multiple. Postcontrast MRI can be particularly helpful, including when attempting to differentiate the long-segment myelopathy of neurosarcoidosis and aquaporin-4 (AQP4)-IgG-seropositive neuromyelitis optica spectrum disorder (NMOSD) and when characterizing spinal cord tumors such as primary neoplasms and metastases. Spinal dural arteriovenous fistula is another do-not-miss diagnosis, with characteristic MRI features both precontrast and postcontrast. Tract-specific white matter involvement can be a clue for diseases such as subacute combined degeneration, paraneoplastic myelopathy, and radiation myelitis, whereas gray matter-specific involvement can suggest conditions such as cord infarct, viral myelitis, or myelin oligodendrocyte glycoprotein (MOG)-IgG associated disorder.
Knowledge of the neuroimaging findings of the many causes of spinal cord and cauda equina dysfunction is critical for both neurologists and neuroradiologists. A structured approach to lesion compartmental location and imaging feature characterization is recommended.
本文回顾了脊髓和马尾神经疾病的神经影像学表现，重点是 MRI。采用解剖方法；考虑了硬膜外、硬膜内-髓外和髓内（实质）腔室的疾病，涵盖了肿瘤性和非肿瘤性疾病。突出显示了具有鉴别意义的影像学特征。
尽管脊髓的 T2 高信号异常可能有无数病因，但神经影像学可以在许多情况下提供特定的诊断或大大缩小鉴别诊断范围。压迫脊髓的硬膜内-髓外病变的鉴别诊断有限，通常为良性；脑膜瘤和神经鞘瘤最常见。硬膜外病变通常可以明确诊断。椎间盘突出是硬膜外间隙最常见的肿块。颈椎脊髓病可引起特征性增强模式，可能与内在脊髓病混淆。硬膜外间隙不容错过的诊断是特发性脊髓疝，其外观可与蛛网膜囊肿和网重叠。关于脊髓病的内在原因，多发性硬化症的病变特征是短节段，但多个病变可以融合。增强后的 MRI 尤其有帮助，包括在试图区分神经结节病的长节段脊髓病和水通道蛋白-4（AQP4）-IgG 阳性视神经脊髓炎谱系障碍（NMOSD）以及特征性脊髓肿瘤（如原发性肿瘤和转移瘤）时。脊髓动静脉瘘也是另一个不容错过的诊断，具有特征性的 MRI 表现，无论是在对比前还是对比后。束状特异性白质受累可能是亚急性联合变性、副肿瘤性脊髓病和放射性脊髓炎等疾病的线索，而灰质特异性受累可能提示脊髓梗死、病毒性脊髓炎或髓鞘少突胶质细胞糖蛋白（MOG）-IgG 相关疾病等情况。
了解许多导致脊髓和马尾神经功能障碍的病因的神经影像学表现对神经科医生和神经放射科医生都至关重要。建议采用一种结构化的方法来对病变部位和影像学特征进行描述。
