الفهرس 
Diagnosis of Spinal TumorsOnly 14 pages are availabe for public view
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Abstract
SCNs can be divided into extradural and intradural tumors on the basis of their relation to the thecal sac that surrounds the spinal cord and cauda equine. Spinal tumors can occur inside the spinal cord. These are termed intramedullary tumors (e.g., astrocytoma, ependymoma, hemangioblastoma). They may occur within the meninges and are termed intradural extramedullary tumors (e.g., schwannoma, meningioma). They can also arise between the meninges and the bony confines of the spine and are termed extradural (e.g., primary and secondary tumors). The most common tumors that metastasize to the spine are tumors of the lung, breast, prostate, kidney, lymphoma, melanoma, and gastrointestinal tract. Positron emission tomography (PET) images are produced after the injection of trace amounts of radionuclides that have been produced in a cyclotron and concentrate in areas of increased metabolic activity including tumors and various organs. Fluorine-18 fluorodeoxyglucose PET has been shown to have a high predictive value in differentiating spinal metastases from benign lesions. Surgery is indicated to obtain tissue diagnosis, and to perform a radical removal of the neoplasm with preservation or improvement of neurological function. Since the majority of intradural extramedullary tumors are benign and since most of them are well circumscribed and show a clear demarcation to spinal cord tissue, surgery offers excellent chances for total removal and therefore is the therapy of choice for these lesions. Most intradural extramedullary tumors can be operated via the standard postero- or posterolateral approach. In conformal treatments, a large number of convergent beams are directed at a target so that no single beam carries much of the radiation dose. In this situation, very little damage is done to tissues as an individual beam traverses the body. The high-dose region can be shaped to match the target lesion “like a glove.” This can be accomplished in a variety of ways such as an array of fixed isocentric beams, rotational arcs, or multiple non-coplanar beams. Because such large doses of radiation are administered, spinal radiosurgery, requires extremely accurate targeting. In contrast, the lack of precision in conventional external beam radiation therapy and the limitations of target immobilization techniques generally preclude large, single-fraction irradiation near radiosensitive structures, such as the spinal cord. Chemotherapy may be used in the treatment of recurrent intramedullary tumors. Recent studies, however, have shown excellent response of intramedullary spinal cord tumors to chemotherapy, and the subsequent avoidance of radiation therapy, especially in children. Metastatic spinal cord compression (MSCC) is estimated to develop in approximately 5% to 14% of all cancer patients. MSCC is considered a medical emergency, and immediate intervention is required. High-dose corticosteroids and initiation of radiotherapy or surgery are critical in the management of MSCC. However, chemotherapy may have a role in treatment of chemosensitive tumors.