Introduction: Intradural/extramedullary tumors comprise nearly half of all intraspinal tumors and 20% are intramedullary tumors. Intradural tumors remain a challenging problem when deciding the correct procedure.

Methods: We are presenting an algorithm for decision-making regarding the need for surgery and the surgical approaches, based upon anatomy and unique surgical factors.

Results: RASMA is the acronym for the algorithm based upon the following five components: Radiological diagnosis, Axial dorso-ventral location, Sagittal extent of the tumor, Medullary or extramedullary component, Approach towards surgery. A posterior midline approach with laminectomy can be utilized for most posterior or posterolateral lesions. For a posterior midline myelotomy, the dura is opened in the midline providing the safest approach for intramedullary lesions. A posterolateral lesion may be approached through the dorsal root entry zone. The plane of cleavage leads to substantia gelatinosa at the posterior and medial aspect of the dorsal root. For lateral lesions, a more liberal bony removal involving facetectomy and removal of pedicles may be needed. Division of dentate ligaments with gentle traction provides further visualization of the lateral aspect of the spinal cord. Anterior lesions that reach the pial surface may be approached with excision of the vertebral body. Anterior myelotomy can be associated with significant vascular injury to the spinal cord with devastating results. A transthoracic (or possibly thoacoscopic) approach may be applied for ventrally located thoracic tumors. A posterolateral sulcus approach may be offered for intramedullary tumors situated eccentric or laterally in the spinal cord that do not contact the pial surface at the posterior midline or laterally.

Conclusions: The primary deciding factor for surgery in tumors of the spinal cord remains the location of the lesion. The goal of modern surgery for a spinal cord tumor is to provide a safe resection that minimizes neurological deficits.

Patient Care: RASMA provides a framework that facilitates decision-making and can improve patient care.

Learning Objectives: By the conclusion of this session participants should be able to: 1)Various intradural tumor in the spinal cord 2)Surgical decision making for tumors within the spinal cord 3)Approach for surgical resection in intradural tumors

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