title: Surgical results of an endoscopic endonasal approach for clival chordomas.
abstract: BACKGROUND
  The surgical approaches for clival chordomas remain controversial, although the extent of resection is one of the most important factors for long survival rates. Recently an endoscopic endonasal approach in good collaboration with otolaryngologists has attracted major attention as a surgical approach for clival chordomas. We describe our experience with the endoscopic endonasal approach and provide a review of the literature.
  
  
  METHODS
  Between 2008 and 2011, six operations were performed via the endoscopic endonasal approach for clivus chordomas. The mean tumor size was 35 mm in diameter. The tumor location was mainly from the upper to middle clivus. The tumor extended into the cavernous sinus in five cases and intradurally in three cases. A binostril approach was performed in four cases, while a one nostril approach was performed in two cases.
  
  
  RESULTS
  Gross total removal was achieved in three cases. The analysis of cases with incomplete resection suggested that residual tumors were observed epidurally and subdurally. The residual on the epidura was observed from the posterior clinoid to the posterior compartment of the cavernous sinus. On the other hand, the residual on the subdural was observed behind the upper part of the pituitary gland. There was no postoperative cerebrospinal fluid (CSF) leakage using vascularized nasoseptal flaps in any of the cases.
  
  
  CONCLUSIONS
  The endoscopic endonasal transclival approach allows an appropriate extent of resection with acceptable complication rates in comparison with other approaches. In our series, the accomplishment of gross total removal was associated with the relationship between the tumors and surrounding structures, such as the pituitary gland and the cavernous portion of the intracranial carotid artery (ICA).
authors.affiliation: Department of Neurosurgery, Keio University School of Medicine, Shinjuku-ku, Tokyo, Japan. s.katsuya@hotmail.co.jp
authors.forename: Katsuya
authors.initials: K
authors.lastname: Saito
authors.forename: Masahiro
authors.initials: M
authors.lastname: Toda
authors.forename: Toshiki
authors.initials: T
authors.lastname: Tomita
authors.forename: Kaoru
authors.initials: K
authors.lastname: Ogawa
authors.forename: Kazunari
authors.initials: K
authors.lastname: Yoshida
mesh_terms: D000328:Adult; D000368:Aged; D002817:Chordoma / Q000473:pathology / Q000601:surgery*; D003388:Cranial Fossa, Posterior / Q000473:pathology / Q000601:surgery*; D004724:Endoscopy / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D019635:Neurosurgical Procedures / Q000379:methods*; D019292:Skull Base Neoplasms / Q000473:pathology / Q000601:surgery*; D016896:Treatment Outcome