Needle aspiration of intramedullary and intradural extramedullary masses of the spinal canal

Ten intramedullary and 2 intradural extramedullary masses of the spinal canal were evaluated with 16 separate needle aspirations. Cord fluctuance at air myelography and/or low density within the cord on computed tomography determined the level of aspiration. The condition of 2 patients with cystic neoplasms and one with syringohydromyelia improved after fluid removal. Endomyelography demonstrated the extent of 8 intramedullary cavities. In syringohydromyelia, this information was used in determining the surgical approach. Aspiration and tissue biopsy enabled successful diagnosis of 2 cases of intradural extramedullary masses of unknown etiology. Needle aspiration yields valuable diagnostic information and is safe when proper guidelines are followed.