MRI (with and without contrast) plays an essential role in the diagnosis of primary spinal cord tumors. Currently, no other imaging modality can be utilized alone to establish a diagnosis. Plain X-rays may show scalloping in rare cases of long-standing intramedullary tumors, and CT myelography may show spinal cord enlargement in cases of intramedullary tumors. However, the internal structure of the spinal cord and tumor as well as the tumor/cord interface cannot be visualized with those modalities.

The presence of mass effect in the form of spinal cord segmental enlargement, cyst formation, contrast enhancement, and peritumoral edema favors the diagnosis of a neoplastic process. Tumor mimicking diseases are multiple sclerosis, transverse myelitis, spinal cord ischemia, cavernous malformation, sarcoid, and CNS angiitis [1] and should be considered as part of the differential diagnosis. Acute demyelination, for example, in multiple sclerosis and transverse myelitis, may be associated with spinal cord edema and segmental enlargement resembling tumor. Additional studies such as brain MRI, CSF analysis, and angiography should be performed in suspected cases to establish the correct diagnosis. In rare cases when diagnosis cannot be established on the basis of clinico-radiological data, patient observation with follow-up imaging in 2–3 months is a reasonable option. The absence of lesion progression, diminished enhancement, and edema on interval MRI favor nonneoplastic process.

Microsurgery is the cornerstone of spinal cord tumor treatment. It has been shown that tumor type and grade are the most important factors affecting outcome (Table 18.3). Surgery provides tissue sampling and consequently, a pathological diagnosis with corresponding prognosis as well as cytoreduction. In the majority of well-defined (circumscribed) low-grade tumors, resective surgery can be curative. In instances of infiltrative tumors, maximal safe resection or biopsy contributes to management by providing diagnosis and defining further treatment. In addition to standard contrast MRI, diffusion tension tractography is a useful tool that can show the passage of fibers around or though the tumor and therefore can be used as part of the preoperative planning [8]. Functional MRI (fMRI), widely used for preoperative planning in eloquent brain areas, has not been utilized for spinal cord tumors, though application for other pathologies such as traumatic injury or multiple sclerosis has yielded encouraging results [4].

Extent of resection has a positive correlation with patient outcome. However, this strategy is counterbalanced with the risk of neurologic injury from aggressive surgery. Most postsurgery deficits are transient and improve with time and rehabilitation. McCormick proposed a grading system of spinal cord tumors and showed that the patient’s functional status and limited longitudinal extent of the tumor are the most favorable preoperative functional outcome factors. Delayed postoperative neurological deterioration may occur due to tumor growth (most frequent) or from operative complications such as spinal cord tethering to the dura, spinal instability, and resulting kyphotic deformity. Spinal instability may be present pre- or postoperatively and results from neurologic deficits causing an axial deformity, post-laminectomy kyphosis, radiation injury, syringomyelia, or combination of these factors. Some studies showed an advantage of laminoplasty over laminectomy for prevention of future deformity at least in the pediatric population. This effect seems to be less prevalent in the adult group, though laminoplasty facilitates surgical exposure in recurrent cases. Yasargil et al. reported his series with intraspinal AVMs and tumors approached via hemilaminectomy [10]. Though technically challenging, this approach ultimately eliminates the risk of surgery-induced instability, especially in junctional regions of the spine. Postoperative spinal cord tethering to durotomy site is not infrequent and may be the cause of significant neuropathic pain and deficit. Midline myelotomy, pial suturing after tumor resection, may decrease the likelihood of tethering and should be performed whenever feasible. Reoperation with allo- or autografts usually fails to treat the condition since the granulation tissue inevitably grows into the graft and spinal cord itself. Artificial inert materials, such as Goretex, are an excellent alternative, and in our experience prophylactic grafting at the time of first surgery reduces the risk of tethering (Fig. 18.2).

Radiotherapy is an important adjuvant therapy for the treatment of spinal tumors. Radiotherapy is primarily administered for high-grade gliomas and for recurrent or residual tumors with confirmed progression when surgical resection is deemed not possible. Radiotherapy-associated side effects are characterized as acute, early delayed, and late delayed. Acute reactions usually reflect secondary inflammatory and transient effects on nearby tissues (in-field effects) especially skin and gastrointestinal. Early delayed side effects most often manifest as transient demyelination and commonly posterior column dysfunction (i.e., Lhermitte’s sign) that can be seen on T₂-weighted images. Delayed late injuries include secondary malignancies particularly in the pediatric population and patients with genetic tumor predisposition disorders.