title: The endoscopic endonasal approach for extradural and intradural clivus lesions.
abstract: OBJECTIVE
  To report the use of the endoscopic transnasal transclival approach to treat tumors involving the clivus region.
  
  
  METHODS
  The clinical records of 38 patients with clivus lesions were retrospectively reviewed to determine the surgical technique used. All patients were surgically treated using any of the options of the endoscopic transnasal transclival approach at the São Paulo Skull Base Center from 2000-2011. A transsphenoidal, transpterygoidal, retropharyngeal, or a combination of approaches was chosen based on the tumor topography.
  
  
  RESULTS
  Chordomas were the most frequent tumor (26 of 38), followed by chondrosarcoma (2 of 38). Biopsy only was performed in 6 patients with metastasis to the clivus, and 1 patient with fibrous dysplasia underwent a planned partial resection. Gross total resection (GTR) was achieved in 15 of 31 (48%) patients with indications for GTR. For centrally located tumors, GTR was achieved in 75% (15 of 20 patients). Fistula was the most frequent complication (6 of 31; 19%) but was much lower in the most recent series using the nasoseptal flap (1 of 16; 6%). Tumors with lateral extensions or with previous treatment had the worst results. The presence of intradural extension was not a limiting factor for GTR.
  
  
  CONCLUSIONS
  Endoscopic transnasal surgery is an alternative approach to treatment of clivus lesions, and, in expert hands, this technique can obtain good results. Lateral extension and previous treatment were factors that could make the surgery more difficult. Intradural extension did not limit the radicality of the removal.
authors.affiliation: DFV Neurosurgery, São Paulo, Brazil; São Paulo Skull Base Center, São Paulo, Brazil. Electronic address: evellu@terra.com.br.
authors.forename: Eduardo de Arnaldo Silva
authors.initials: Ede A
authors.lastname: Vellutini
authors.affiliation: São Paulo Skull Base Center, São Paulo, Brazil; Department of Otolaryngology, Head and Neck Surgery, Federal University of São Paulo, São Paulo, Brazil.
authors.forename: Leonardo
authors.initials: L
authors.lastname: Balsalobre
authors.affiliation: São Paulo Skull Base Center, São Paulo, Brazil.
authors.forename: Diego Rodrigo
authors.initials: DR
authors.lastname: Hermann
authors.affiliation: São Paulo Skull Base Center, São Paulo, Brazil; Department of Otolaryngology, Head and Neck Surgery, Federal University of São Paulo, São Paulo, Brazil.
authors.forename: Aldo Cassol
authors.initials: AC
authors.lastname: Stamm
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D003388:Cranial Fossa, Posterior / Q000601:surgery*; D004388:Dura Mater / Q000601:surgery*; D004724:Endoscopy / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009296:Nasal Cavity / Q000601:surgery*; D019635:Neurosurgical Procedures / Q000379:methods*; D011183:Postoperative Complications / Q000453:epidemiology; D012189:Retrospective Studies; D019292:Skull Base Neoplasms / Q000601:surgery*; D055815:Young Adult
keywords: Chordoma; Clivus; Endonasal; Endoscopic