Intramedullary melanotic schwannoma of the cervical spine: A case report and literature review.

Intramedullary melanotic schwannomas (IMS) are rare lesions, with only 8 cases reported in the literature to date. We herein describe the case of a 40-year-old male patient with an IMS of the cervical cord, which, to the best of our knowledge, is the ninth reported case of IMS, and review the relevant literature. The patient presented with numbness of the left arm that gradually worsened over a period of 4 months. Magnetic resonance imaging (MRI) of the cervical spine with gadolinium enhancement revealed an intramedullary lesion at the level of C1-C2. The mass was T1 hyperintense, T2 hypointense and homogeneously enhanced. During surgery, an intramedullary dark gray lesion was identified and was partially removed. The left arm numbness partially subsided 2 weeks after surgery. Although rare, IMS is associated with characteristic MRI findings (T1 hyperintensity, T2 hypointensity and homogeneous enhancement) and MRI is the preferred method for evaluating lesions of the spinal cord. Correct diagnosis is crucial for management planning; therefore, immunohistochemical examination is required. In addition, IMS cases must be closely followed up, particularly when the mass cannot be completely resected.