title: Thoracolumbar intramedullary subependymoma with multiple cystic formation: a case report and review.
abstract: BACKGROUND
  An intramedullary subependymoma is rare, particularly in the thoracolumbar region. Moreover, a radiographical obvious cystic formation of subependymoma of spinal cord rarely occurs in comparison to ependymoma.
  
  
  METHODS
  A 57-year-old woman presented with paraparesis. MRI revealed a multinodular and multicystic lesion in the spinal cord that was difficult to diagnose correctly. Intraoperative observation via midline myelotomy revealed a grayish, gelatinous solid mass with an eccentric localization. In addition, DREZtomy on the caudal side of the tumor revealed cystic formation. The cyst was punctured and xanthochromic fluid was collected. Attenuation of motor evoked potential (MEP) resulted in the partial removal of tumor. A pathological examination revealed the mass to be a subependymoma. The patient experienced transient worsening of symptoms, but improved gradually. No adjuvant radiosurgery was administered. Follow-up estimation 30 months after surgery revealed no evidences of regrowth.
  
  
  CONCLUSIONS
  This report presents this rare case, a review of the literature associated with thoracolumbar subependymomas, and a discussion of the clinical and radiographical characteristics.
authors.affiliation: Department of Neurosurgery, Hokkaido University Graduate School of Medicine, North 15 West 7, Kita-ku, Sapporo, 060-8638, Japan. jzesso801@yahoo.co.jp
authors.forename: Motoyuki
authors.initials: M
authors.lastname: Iwasaki
authors.forename: Kazutoshi
authors.initials: K
authors.lastname: Hida
authors.forename: Takeshi
authors.initials: T
authors.lastname: Aoyama
authors.forename: Kiyohiro
authors.initials: K
authors.lastname: Houkin
mesh_terms: D003560:Cysts / Q000473:pathology* / Q000601:surgery; D005260:Female; D018315:Glioma, Subependymal / Q000473:pathology* / Q000601:surgery; D006801:Humans; D008159:Lumbar Vertebrae; D008875:Middle Aged; D013120:Spinal Cord Neoplasms / Q000473:pathology* / Q000601:surgery; D013904:Thoracic Vertebrae