title: Tumor origin and hearing preservation in vestibular schwannoma surgery.
abstract: OBJECTIVE
  Preservation of cochlear nerve function in vestibular schwannoma (VS) removal is usually dependent on tumor size and preoperative hearing status. Tumor origin as an independent factor has not been systematically investigated.
  
  
  METHODS
  A series of 90 patients with VSs, who underwent surgery via a suboccipitolateral route, was evaluated with respect to cochlear nerve function, tumor size, radiological findings, and intraoperatively confirmed tumor origin. All patients were reevaluated 12 months after surgery.
  
  
  RESULTS
  Despite comparable preoperative cochlear nerve status and larger tumor sizes, hearing preservation was achieved in 42% of patients with tumor originating from the superior vestibular nerve, compared with 16% of those with tumor originating from the inferior vestibular nerve.
  
  
  CONCLUSIONS
  Tumor origin is an important prognostic factor for cochlear nerve preservation in VS surgery.
authors.affiliation: Department of Neurosurgery, Martin-Luther-University of Halle-Wittenberg, Halle, Germany. jens.rachinger@medizin.uni-halle.de
authors.forename: Jens
authors.initials: J
authors.lastname: Rachinger
authors.forename: Stefan
authors.initials: S
authors.lastname: Rampp
authors.forename: Julian
authors.initials: J
authors.lastname: Prell
authors.forename: Christian
authors.initials: C
authors.lastname: Scheller
authors.forename: Alex
authors.initials: A
authors.lastname: Alfieri
authors.forename: Christian
authors.initials: C
authors.lastname: Strauss
mesh_terms: D000328:Adult; D000368:Aged; D003056:Cochlear Nerve / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery; D005154:Facial Nerve / Q000502:physiology / Q000503:physiopathology / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D034381:Hearing Loss / Q000503:physiopathology / Q000517:prevention & control* / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D009464:Neuroma, Acoustic / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D019635:Neurosurgical Procedures / Q000009:adverse effects*; D012189:Retrospective Studies; D016896:Treatment Outcome